Abstract
William G. (‘Bill’) Chaloner FRS (1928–2016) was one of the world’s leading palaeobotanists and palynologists. He developed a love of natural science at school which led to a penchant for palaeobotany at university. Bill graduated in 1950 from the University of Reading, and remained there for his PhD, supervised by Tom Harris, on the spores of Carboniferous lycopods. After completing his PhD in 1953, Bill undertook a postdoctoral fellowship in the USA. He returned to the UK and, in 1956, began a long and distinguished academic career at four colleges of the University of London. His first position was at University College London, where he continued to work on Paleozoic palaeobotany and palynology. His 1958 paper on the effects of fluctuating sea levels on Carboniferous pollen-spore assemblages proved highly influential. Bill moved to a Chair at Birkbeck College in 1972, began to use the scanning electron microscope and was elected a Fellow of The Royal Society in 1976. He is the only pre-Quaternary palynologist to have been given the latter honour. In 1979, Bill was appointed to the Chair of Botany at Bedford College where he began to apply plant fossil evidence to general scientific problems. He began to work on arthropod–plant interactions, fossil charcoal and growth rings in wood. Bill was awarded the Medal for Scientific Excellence by the American Association of Stratigraphic Palynologists in 1984. Bedford College and Royal Holloway College merged in 1985, and Bill moved to the amalgamated institution. Bill continued to investigate very diverse topics, and added the analysis of leaf stomata, global environmental change and molecular palaeontology to his portfolio. Following retirement in 1994, Bill continued his research and teaching at Royal Holloway, University of London. His final paper was published in 2016, bringing to an end a research career of 66 years.
1. Introduction
The closely associated disciplines of palaeobotany and palynology lost one of their most distinguished and influential exponents when Professor William Gilbert (‘Bill’) Chaloner passed away at his home in Sheen, Surrey, England, on 13 October 2016 at the age of 87. Bill Chaloner had a stellar career in the world of fossil plants and palynomorphs. His 176 publications were consistently innovative, perceptive and wide ranging, and had substantial impact (Supplemental data, Appendix 1). He was a member of the teaching staff at four colleges of the University of London between 1956 and his formal retirement in 1994. In 1976 Bill was elected a Fellow of The Royal Society (FRS), only the second palynologist in that society after Sir Harry Godwin. Bill received many honours including being made the second recipient of the American Association of Stratigraphic Palynologists (AASP) Medal for Scientific Excellence in 1984. He was also awarded the Linnean Gold Medal for Botany in 1991, the Lyell Medal of the Geological Society in 1993 and the Lapworth Medal by the Palaeontological Association in 2005. Previous accounts of Bill Chaloner’s life include Scott and Collinson (Citation1993) and Traverse (1993) in a volume of invited papers by Bill’s collaborators and students commemorating his retirement from Royal Holloway, University of London (RHUL) (Collinson and Scott Citation1993). Other tributes have been published since his death (Scott Citation2016a, Citation2016b, Citation2016c, Citation2018a; Collinson Citation2017; Pearson Citation2017; Scott and Crane Citation2018), and a radio appreciation on BBC Radio 4’s Last Word was broadcast on 16 December 2016 (http://www.bbc.co.uk/programmes/b006qpmv/episodes/downloads). This biography and obituary seeks to document and celebrate his long, fulfilling and productive life (). All the species names quoted in this work are listed, with their author citations, in the Appendix.
Table 1. A tabulated synopsis of Bill Chaloner’s principal career milestones.
2. Early life and education (1928 to 1947)
Bill Chaloner was a Londoner all his life; aside for a few years, he never moved out of Greater London. He was born in Chelsea, west London, on 22 November 1928, the fourth child of two journalists, Ernest J. and Lenore (‘Len’; née Sybil Maude Barling) Chaloner. Ernest Chaloner was the London Editor of the Journal of Commerce; Lenore Chaloner was in magazines and published Ideal Home, Parents and Woman’s Magazine. Journalism and publishing were very strong traits in the Chaloner family; Bill’s elder brother John Seymour Chaloner (1924–2007) co-founded the German weekly current affairs magazine Der Speigel (‘The Mirror’) after World War II (WWII) in 1947, and was the author of children’s books and novels. John Chaloner’s obituary was published in The Times on 17 February 2007. It seems that geology was in Bill’s DNA, perhaps because of his connection to the famous English geologist Charles Lapworth (1842–1920). The son of Charles Lapworth, Herbert Lapworth (who was also a geologist), was the husband of a first cousin of Lenore Chaloner, Bill’s mother. Bill always kept in touch with the Lapworth family despite this relatively distant familial relationship.
As a child, Bill lived on King’s Road in Chelsea, and attended Kingston Grammar School (KGS) in south-west London. He began his studies in the autumn of 1941, two years into WWII, and took his School Certificate there. Bill vividly recalled V1 flying bombs and V2 rockets from June 1944 to the end of WWII. His love for the natural sciences began at school, and he went on to take the Higher School Certificate (the equivalent of current A-levels in England and Wales). For the Higher School Certificate, Bill studied applied and pure mathematics, chemistry and physics. It was not possible to take biology at KGS, which he was very keen to do. So, upon leaving KGS in 1946, Bill attended evening classes at Chelsea Polytechnic on Manresa Road to study Higher School Certificate botany and geology for one year following the strong encouragement of his early mentor, William Fleet. Chelsea Polytechnic later became Chelsea College, University of London, and, in 1985, merged with the nearby Queen Elizabeth College and King’s College London, keeping the name of King’s College London. Bill much preferred these subjects to the physical sciences he studied at school. At Chelsea, Bill found his introduction to both botany and geology fascinating, especially the extensive fieldwork. He particularly appreciated William Fleet’s lectures on geology, and met other like-minded people, including his subsequent collaborator Geoffrey T. Creber. Bill was mentored in palaeobotany by Herbert Duerden and William Fleet. The former recommended Marie Stopes’s classic textbook Ancient Plants (Stopes Citation1910), which inspired Bill greatly and confirmed his enduring interest in fossil floras. What especially intrigued him about palaeobotany was that geology provided a time dimension to plant evolution. Bill found his first fossil plants on a field trip to the London Clay Formation (Ypresian) of the Isle of Sheppey, where he collected pyritised fruits of the palm Nypa.
3. The undergraduate (1947 to 1950)
While he was at Chelsea, by then 18 years old, Bill successfully took the scholarship for the University of Reading in 1947 to study botany, chemistry and geology with the idea of going into agriculture. This was a masterstroke as, during the first years of peacetime, ex-service personnel were given substantial preference over civilians who had not yet done their two years of National Service. The leverage of the Wantage Scholarship propelled Bill into Wantage Hall at Reading, where his residence fees were paid. This meant that his parents had only to pay the tuition fees of £30 per annum. In 1949, after two years, Bill was awarded a first class general bachelor’s degree in botany, chemistry and geology. Under the mentorship of Professor Thomas Maxwell (‘Tom’) Harris FRS (1903–1983), who was then Head of the Department of Botany, the general degree was followed, during 1950, by first class special honours in botany. Harris was a palaeobotanist who specialised in the macrofloras from the Upper Triassic to Lower Jurassic of East Greenland and the Middle Jurassic of Yorkshire (Chaloner Citation1985a and references therein). Ironically, Bill studied extant plants during his honours year because Tom Harris insisted that, if one wished to research fossil plants (which Bill really wanted to do), one should keep out of it as an undergraduate. Consequently, Bill studied aspects such as algal counting, fungi, lake ecology, plant ecology, plant physiology and water analysis, all of which he found fascinating.
Tom Harris was also a friend to his students, and Bill dined with the Harris family many times during his undergraduate days. At Reading, the undergraduates ran a Botanical Society (Botsoc) which Harris controlled in a thoroughly undemocratic, yet benign, manner. The undergraduate president and committee were purely notional. Botsoc would organise field trips by bicycle from Reading to study, for example, ecology and fungi, and to record humidity and temperature in woodlands. Bill was struck by Harris’s preference for somewhat disheveled fieldwork clothing, and adopted this style himself. At the end of each day Harris would invite the students to his home for tea. These were very generous gestures because food was rationed in the UK from WWII to 1954, and also in that Harris was not an inherently gregarious man (Chaloner Citation1985a, p. 237–238). Immediately after graduating Bill worked in Smedley’s pea canning factory in Wisbech, Cambridgeshire, for the princely wage of £5 per week, plus his accommodation and food, during the summer of 1950.
It is clear that many of Bill’s characteristic traits developed during his school and undergraduate years. These included a clear love of natural science in general and botany/palaeobotany in particular, plus broad scientific foundations/polymathy, dealing with austerity, hard work, initiative, a penchant for fieldwork and the outdoor life, sociability, and a strong sense of purpose.
4. Research student (1950 to 1953)
Bill Chaloner decided to undertake a PhD starting in the autumn of 1950. He had in mind to investigate the Reading Formation (Lambeth Group) of south-east England, of Palaeocene age (Ellison et al. Citation1994). Bill had collected leaf and seed fossils from this unit but was dissuaded by Tom Harris, who did not have the expertise on angiosperm systematics to supervise this work. This topic was later researched by Sir Peter R. Crane FRS. So it was that Tom Harris successfully bid for a Department of Scientific and Industrial Research (DSIR) grant for Bill to work on Carboniferous plants with him. Specifically, this work was to compare dispersed and in situ spores from Carboniferous lycopods. Bill had to extract spores from lycopod cones, and this would therefore help to establish the parent plants of dispersed spores. By integrating palaeobotany and palynology this research elucidated fundamental palaeoecology, and Bill successfully used the concept of comparing megafossils and microfossils throughout his long scientific career. In addition to his research, Bill was a graduate demonstrator at Reading; this clearly developed his teaching skills, as well as supplementing his limited income. Notably, Bill demonstrated to Harold W. Woolhouse (1932–1996) who went on to become Professor of Botany at the universities of Leeds and East Anglia.
A substantial stimulus to Bill’s research into in situ megaspores and microspores was Moore (Citation1946). This paper, by Leslie R. Moore (1912–2003) who was the founder of the famous school of palynology at the University of Sheffield (Spinner et al. Citation2004; Wellman Citation2005), was on assemblages of spores extracted from Carboniferous plant compression fossils. These relatively sparse associations comprised several species. Moore (Citation1946, ) interpreted these assemblages as representing several developmental stages in a coherent ontogenetic series of spores. This conclusion is now disproved, the variety of spores being due to the contamination of the macrofossil specimens by the surrounding sediment (Crookall et al. Citation1948). Bill found that, in megaspores, contamination was negligible; the large masses of homogeneous spore types made the introduction of allochthonous forms very remote indeed. Unfortunately, this minor controversy around Moore’s spore-development theory caused some friction between Sheffield and other laboratories, including Bill at Reading and later at University College London (UCL). Happily, in later years, the animosity about the spores in situ issue dissipated, and Bill went on to have very amicable relations with Sheffield colleagues such as George Hart, Roger Neves, John Richardson and Charles Wellman, and frequently was an external examiner there. One of the Sheffield PhD students that Bill subsequently examined was Alan Marshall, who did similar doctoral research to Bill. For example, Alan Marshall compared the spores in palaeosols (seat earths) with those in the overlying coal seams.
Figure 1. A dapper, suited and booted Bill Chaloner in front of his 1948 pea-green Buick Roadmaster while on a road trip from Ann Arbor to California and back in the spring of 1954 (section 7). Precise date and photographer unknown. The image is reproduced with the approval of the Chaloner family.
Figure 2. Bill and Judy Chaloner’s wedding at Chelsea Town Hall, London in 1955 (sections 7 and 8). Photographer unknown. The image is reproduced with the approval of the Chaloner family.
Figure 3. Bill Chaloner in the army in 1955, age 27, wearing the uniform of the Thirtieth Royal Artillery Regiment during his National Service (section 8). Precise date and photographer unknown. The image is reproduced with the approval of the Chaloner family.
Figure 4. A young Bill Chaloner, probably early in his career at University College London in 1956 (section 9). Precise date and photographer unknown. The image is reproduced with the approval of the Chaloner family.
Figure 5. A diagrammatic representation of the Neves effect (subsection 9.3; Chaloner Citation1958e, Citation1961; Chaloner and Muir Citation1968). The three numbers to the right (43, 50 and 72) represent the total number of pollen-spore species in each setting, and are taken from Neves (Citation1958). In the topmost and centre panels (1 and 2), sea levels are low and the pollen-spores of hinterland plants (largely Florinites pollen derived from trees bearing Cordaitanthus pollen organs) are markedly subordinate to the highly abundant microspores produced by Lepidostrobus (Lycospora) which characterise the low-lying coal swamp and the non-marine shale settings. Note that the non-marine shale environment represents local submergence of the coal swamp; the consequent input of pollen-spores via water and wind explains the slightly higher diversity. By contrast, in the lowermost panel (3), sea levels are relatively high and the marginal, low-topography coal swamp vegetation, dominated by Lepidodendron, has been virtually all inundated. This means that relatively far-travelled, water- and wind-borne (hinterland) Florinites pollen is now the dominant element in a substantially more diverse association. Adapted from Chaloner and Muir (Citation1968, fig. 4).
Figure 6. Bill Chaloner in his academic robes at a graduation day parade during his secondment to the University of Nigeria at Nsukka between 1965 and 1967 (subsection 9.7.1). Precise date and photographer unknown. The image is reproduced with the approval of the Chaloner family.
Figure 7. Bill Chaloner and Andrew C. Scott at Kiltorcan Quarry, Kilkenny, Ireland on fieldwork in early 1978 (subsection 10.2). Bill and his collaborators have worked extensively on this important locality, which exposes an Upper Devonian succession. For example, Chaloner et al. (Citation1977) discovered the earliest seed plants from the British Isles from Kiltorcan. Precise date and photographer unknown. From the photograph collection of Andrew C. Scott.
Figure 8. Left to right, Bill Chaloner, Al Traverse and Paul K. Strother pictured on fieldwork in the USA in the spring of 1981 (subsection 11.1). At this time, Paul Strother was a postdoctoral fellow with Elso Barghoorn at Harvard University, USA. The three are pictured in central Pennsylvania, USA, where they were revisiting outcrops of the Tuscarora Formation (Silurian). Al and Paul had previously reported on a pre-vascular plant terrestrial palynoflora from this lithostratigraphical unit (Strother and Traverse Citation1979). Precise date and photographer unknown. From the photograph collection of Bill Chaloner.
Figure 9. Bill Chaloner at an informal retirement party organised by his students at Royal Holloway, University of London, during the summer of 1994 (subsection 13.1). Bill is pictured making the first slice into a spore cake baked by Alan R. Hemsley; note the prominent trilete mark. Photographer Andrew C. Scott.
Figure 10. Bill Chaloner in retirement, 1991 (subsection 13.1). Precise date and photographer unknown. From the photograph collection of Andrew C. Scott.
Figure 11. Bill Chaloner and Al Traverse at the American Association of Stratigraphic Palynologists (AASP) Business Luncheon held during the 12th International Palynological Congress (IPC) in Bonn, Germany, on the evening of Thursday 4 September 2008 (subsection 13.1). The 41st AASP Annual Meeting was held jointly with the 12th IPC; similarly, the 12th IPC was also held jointly with the 8th International Organisation of Palaeobotany Conference. The annual AASP Business Luncheon is an opportunity for the Board of Directors to present activity reports, give out awards and introduce new board members over a meal. This was the first time it had been held during the evening, and it was a great success. Bill and Al were the informal guests of honour, and received several requests for photographs. This image is of, from left to right, Millerlandy Romero, Al Traverse, Fátima P.R. Leite, Bill Chaloner and Manuel Veira. Photographer: James B. Riding. Two other images from this event are included in Supplemental data, Appendix 4.
Figure 12. Bill Chaloner (centre) with four of his research students, from left to right, Thomas M.F. Windle, Andrew C. Scott, Margaret E. Collinson and Michael C. Boulter (subsection 13.1). Photograph taken at The Royal Society, Carlton House Terrace, London in 2012, photographer unknown. From the photograph collection of Andrew C. Scott.
Tom Harris always emphasised the importance of fieldwork and collecting one’s own samples; consequently, Bill travelled far and wide in the UK. Much of his 1950s fieldwork was around Radstock in Somerset which was the closest accessible coalfield to Reading (Moore and Trueman Citation1937). He had absolutely no funds for travel and subsistence, and had to live on a stipend of £500 per year (the equivalent of around £16,600 in 2018). So Bill hitchhiked to the west country and camped at nearby Mells for two weeks. He collected much material from the colliery spoil heaps including one fertile specimen of Lepidostrobus. The sole contribution of Tom Harris in this endeavour was to send carefully labelled packing cases to Radstock Station for Bill to fill with plant fossils and return to Reading by rail. These fieldwork and sample transport strategies were replicated for Bill’s subsequent fieldwork in the Gloucestershire (Forest of Dean) and Yorkshire coalfields. In the former area, Bill obtained good spore-bearing cone specimens, some connected to leafy shoots. Ironically, the majority (> 75%) of his research material came from museum collections, most notably the British Museum (Natural History) [BM(NH) now the Natural History Museum], London, the Geological Survey Museum, London, the Manchester Museum and the University of Cambridge.
Bill was the president of the University of Reading Students’ Union for the academic year 1951–1952 (section 5). While he was a delegate at the 1952 annual National Union of Students (NUS) Congress held at the University of Manchester, Bill left the doubtless erudite discussions to visit the nearby Manchester Museum. He found on display an especially interesting large (∼2 m long) specimen of Lepidodendron with attached cones on leafy shoots. Bill extracted spores from this magnificent specimen by pressing clear adhesive tape onto the cones and then removing it, with some of the coalified material adhering to the tape. Michael Eager (1919–2003) was then the curator at Manchester Museum, and carefully observed this unusual process with great interest and considerable trepidation. Bill subsequently dissolved the tape and macerated the residue in Schultze’s solution to extract the Lagenicula horrida spores (Chaloner Citation1953a, p. 263, pl. 8.1).
Because Bill lived and worked near London, he had the opportunity to attend the many meetings held at the Geological Society at Burlington House in Piccadilly. There, in 1952, he met the famous author, coal geologist, palaeobotanist, pioneer of birth control and sex education, and social reformer Marie Stopes (1880–1958) at a tea prior to a Geologists’ Association (GA) meeting. She is described as one of the twentieth century’s most remarkable women (Hall Citation1977). Marie was voted Woman of the Millennium by readers of The Guardian newspaper in 1999, she appeared on a UK commemorative postage stamp during 2008 and was selected as the 10th most impactful woman on world history by BBC History Magazine in 2018. Her magnum opus Married Love (Stopes Citation1918a) is considered one of the most significant books of all time (Rayner Citation1991; Bragg Citation2006). This is because she advocated full equality in marriage between men and women, the rights of women to sexual pleasure in marriage, and their choice in conception. Married Love was swiftly followed by a sequel, Wise Parenthood, which was largely about contraception (Stopes Citation1918b). However, between 1903 and 1935, she undertook pioneering research on Carboniferous palaeobotany, coal balls, coal classification and petrology, and fossil angiosperms. The aforementioned GA lecture in 1952 was to be given by the anthropologist Kenneth Oakley, who had been awarded the Henry Stopes Medal for human prehistory by the GA for that year. Henry Stopes, an anthropologist and archaeologist, was Marie’s father. Bill vividly recalled Marie’s striking appearance as she shimmered into the Geological Society library, particularly noting her large garlanded hat and ‘showy’ jewellery, and commented that she was more suited to a reception at Buckingham Palace or the Royal Enclosure at Ascot than a geological gathering (Chaloner Citation1995, p. 128). As he was a second-year postgraduate student at the time, Bill was somewhat bashful when William N. (‘Bill’) Croft, a palaeobotanist at the BM(NH), introduced him to Marie Stopes. However, Marie was delighted to meet a budding palaeobotanist and said to him, in a strident voice which turned heads throughout the packed library, ‘Ah, dear boy, that is wonderful! Of course palaeobotany was my first love’. Despite Bill’s youthful and somewhat naive self-consciousness, his first of several encounters with this remarkable woman made a huge and lasting impression on him (Chaloner Citation1958a, Citation1995, Citation2008). This lifelong fascination with Marie and her work led Bill to brief Ruth Hall, Stopes’s principal biographer, on the ‘mysteries’ of palaeobotany (Hall Citation1977, p. 13). To Bill’s delight, Marie posted him copies of her early papers following their 1952 meeting. Bill reciprocated with Chaloner (Citation1951), and the two entered into sporadic correspondence; Stopes later visited Bill at UCL in 1957 (subsection 9.2.1.).
Tom Harris proved to be an excellent supervisor, and was a highly influential mentor to Bill, and his other research students and collaborators who included Kenneth L. Alvin, Mabel W. Kendall (1920–2004), Olaf Selling and William S. Lacey at this time. Bill socialised with the Harris family a great deal during the tenure of his PhD. He got to know Tom’s wife, Katharine Massey (also a botanist, see Watson Citation2005, p. 250) and four daughters well. Harris was very attentive, and would normally visit Bill daily to keep up with his progress. Tom Harris considered that writing a PhD thesis could engender a tendency to unrestrained verbosity. Bill described Harris as a ‘merciless’ editor who would promptly rewrite initial hand-typed drafts in scrawling pencil script, and produce copious handwritten notes, frequently of greater bulk than the original. During his time as a research student, Bill wrote his first six papers (Chaloner Citation1951, Citation1952, Citation1953a, Citation1953b, Citation1953c, Citation1954a); these were all single-authored, and all on Carboniferous palaeobotany and palynology (Supplemental data, Appendix 1). Harris robustly impressed upon Bill the need for brevity, economy and precision when writing scientific papers. Bill’s PhD was awarded as the result of an examination in 1953 by John Walton (1895–1971). The latter thought it unnecessary to interview Bill in person, and recommended that the degree be awarded on the sole basis of reading the thesis (Chaloner Citation1953d). John Walton was an eminent palaeobotanist based in Glasgow (Pant Citation1972; Braid Citation1973; Liston and Sanders Citation2005). Bill had described a new lycopod fertile organ in his second paper as Lepidocarpon waltonii (see Chaloner Citation1952).
5. Student politics at Reading
Bill Chaloner felt very strongly about politics; he was avowedly very left of centre, and toyed with the idea of joining the Communist Party as a student like so many of his contemporaries. His radical views began at school, and continued while he was at the University of Reading. He was of the view that young people were more leftist in the 1950s and 1960s than afterwards (personal communication to JBR 2002). Perhaps this was an overt reaction to austerity after WWII, and a desire to make the postwar world a better place. From his first undergraduate year at Reading, Bill attended all the Students’ Union meetings.
All Students’ Unions in the UK are affiliated to the NUS. At the time, the NUS had many contacts with countries behind the Iron Curtain, especially the USSR. Bill clearly recalled many delegations of Russian students visiting Reading. These ‘students’ were largely middle-aged and had attentive ‘student minders’; all the visitors explained at length how idyllic student life was in the USSR. Bill enjoyed these wide cultural experiences and discussing the Cold War, but felt that the day-to-day lives of students in the UK, both on and off campus, were often neglected (personal communication to JBR 2002).
Consequently, and despite the reservations of Tom Harris, Bill stood for the position of President of the Reading Students’ Union during the second year of his PhD, the academic year 1951–1952, and was elected. Bill felt that serving the Students’ Union was both duty and vocation. His manifesto was to focus on what concerned ‘students as such’ (a much-used phrase at that time), as opposed to what was going on in the outside world. Bill’s responsibilities included formulating policy, and disbursing the £5000 per year budget given by the university to the many student societies (such as Botsoc) and sports clubs which were affiliated to the Students’ Union (personal communication to JBR 2002).
The Vice-Chancellor of the University of Reading at that time was John F. (‘Jack’) Wolfenden CBE (1906–1985; later Baron Wolfenden). Wolfenden was almost as new to the job as Bill was in his presidency of the Students’ Union, having started in 1950. He was primarily an educationalist, and is best known for chairing the Royal Commission on Homosexual Offences and Prostitution (‘The Wolfenden Committee’) whose report was published in 1957. This helped to achieve the decriminalisation of homosexuality in England and Wales in 1967. Bill and Jack Wolfenden got along famously and they held frequent meetings. These were often impromptu and Bill would typically rush into his secretary’s office and say ‘I must see the Vice-Chancellor’, if a perceived crisis had occurred in student affairs. Wolfenden would normally overhear this exchange, emerge from his inner sanctum and boom, ‘Come on in, Bill’. Bill clearly recalled that Wolfenden’s desk would always be completely clear (this was of course in the pre-digital era!), and that he would be offered a cigarette from a large box. This would naturally be taboo today, but at that time smoking was a sort of catalyst to informal chat. It seemed to Bill that the Vice-Chancellor always made lots of time for him, despite the fact that Wolfenden must have been extremely busy running the university together with his many outside responsibilities.
Bill tremendously enjoyed being President of the Students’ Union and relished multitasking and the contrast with his core task of researching his PhD. He thought that the role with the union helped him later in his career, especially in obtaining a postdoctoral fellowship to the USA (section 7). The Harkness Foundation, which funded the fellowship, were interested in people who reached beyond simply their field of research. Furthermore, this voluntary post, and his close working relationship with Jack Wolfenden, appears to have substantially influenced Bill Chaloner the man. Both apparently strengthened Bill’s already generous and kind spirit towards other people, which shone through in his committee work, scientific collaborations, supervising of research students and teaching in later life.
6. British palaeobotany and palynology in the early 1950s
It is interesting, at this stage, to reflect on the scientific world in which the young Bill Chaloner found himself during his PhD research. Following the death of Albert C. Seward in 1941, there were only two active pre-Quaternary palaeobotanists who were full university professors in the UK during the early 1950s. These were Tom Harris (who was supervised by Albert C. Seward), and John Walton of Glasgow, an expert on the Carboniferous (Liston and Sanders Citation2005). By that time Hugh Hamshaw ‘Ham’ Thomas (1885–1962) at Cambridge, an expert on the Jurassic flora of Yorkshire, had virtually ceased active research, but was still head of the Botany School. Thomas only published five substantive papers after 1950 (Harris Citation1963). The last of these was a joint paper with Tom Harris on cycads from the Jurassic of Yorkshire (Thomas and Harris Citation1960). Quaternary palaeobotany was being researched at Cambridge, led by Harry Godwin (1901–1985) (West Citation1988).
Palaeobotany was being researched in other institutions in the early 1950s. The palaeobotanist Robert Crookall (1890–1981) retired from the Geological Survey of Great Britain (GSGB) in London in 1952, during Bill’s PhD research. Crookall was recruited by the survey in 1924 in order to complete and continue the work of Robert Kidston (1852–1924) (subsection 9.4.). Following his retirement in 1952, Robert Crookall famously went on to investigate out-of-body experiences (e.g. Crookall Citation1968). Among the palaeontologists at the BM(NH) in the early 1950s were the two palaeobotanists Bill Croft and Wilfred Norman Edwards. Bill Croft was an expert on the Devonian (Croft and Lang Citation1942; Croft and George Citation1959), and tragically died in 1953 (Andrews Citation1980). The principal interest of Wilfred Edwards (1890–1956) was the Paleogene/Neogene (Wonnacott Citation1957). There was also a thriving palaeobotany school at the University of Manchester at this time. It was initiated in 1851 and notable researchers there have included Thomas Hick (1840–1896), William H. Lang (1874–1960), Marie C. Stopes (1880–1958), Ernst Frederick Weiss (1865–1953) and William Crawford Williamson (1816–1895) (see Watson Citation2005). Across the Pennines from Manchester, Alan Wesley was also working at the University of Leeds, and pioneered the use of the transmission electron microscope in palaeobotany (Wesley and Kuyper Citation1951).
Following the retirements of Tom Harris and John Walton, palaeobotany in UK universities was later led by, for example, Kenneth L. Alvin, Bill Chaloner, Dianne Edwards, Norman F. Hughes, William S. Lacey and Kenneth R. Sporne. The latter was primarily a neobotanist, albeit one with a great love of palaeobotany. He was based at Cambridge and undertook novel statistical work on correlating plant reproductive and vegetative characteristics of plants in relation to the evolution of angiosperms (Sporne Citation1949). He also published a trilogy of textbooks on vascular plant morphology which included much on palaeobotany (e.g. Sporne Citation1975). The contemporary palaeobotanist Dianne Edwards was supervised by Kenneth Sporne, and has gone on to research aspects of the anatomy and evolution of Silurian and Devonian land plants with great distinction (e.g. Edwards and Kenrick Citation2015). Further analysis on the history of palaeobotany in the UK and elsewhere can be found in Lyons et al. (1995) and Bowden et al. (Citation2005).
Bill Chaloner, the pre-Quaternary palynologist, was in the right place at the right time ploughing a somewhat lone furrow in the early 1950s UK. Charles Downie (1923–1999) also undertook a PhD at the University of Sheffield on the Kimmeridge Clay Formation (Upper Jurassic) of Dorset at this time under the mentorship of Leslie R. Moore (Downie Citation1955, Citation1956; Sarjeant Citation1984; Owens and Sarjeant Citation2000). Prior to the 1950s, there had been some work on Carboniferous spores, for example Raistrick (Citation1933, Citation1934), Florin (Citation1936), Knox (Citation1938, Citation1942), Millott (Citation1939), Moore (Citation1946) and Paget (1947). The work of Arthur Raistrick was especially pioneering in that he used Pennsylvanian (Upper Carboniferous) spores to correlate individual coal seams (Marshall Citation2005). In stark contrast, the Cambridge school, led by Harry Godwin, and others were vigorously researching Quaternary pollen analysis (Manten Citation1967; Nilsson and Praglowski Citation1978; West Citation1988). One difference to today was that there were no specialist journals on palaeobotany and/or palynology in the 1950s. Hence, Bill submitted his early papers to journals such as Annals and Magazine of Natural History, Annals of Botany and Geological Magazine (Supplemental data, Appendix 1).
7. An American postdoctoral fellowship (1953 and 1954)
After successfully obtaining his PhD in 1953, Bill Chaloner was due to be called up for National Service (section 8). However, in the summer of 1953, Bill was awarded a postdoctoral fellowship by the Commonwealth Fund (now termed a Harkness Fellowship). This award funded travel to the University of Michigan at Ann Arbor, USA, and a stipend, to work on Carboniferous lycopods and megaspores from the north-east of the USA with the eminent American palaeobotanist Chester A. Arnold (1901–1977). Arnold (Citation1950) was a highly influential paper on the floras from the Michigan Coal Basin, and so Bill was tremendously excited by this opportunity. The USA was the powerhouse of palaeobotany and palynology in the early 1950s (Riding and Lucas-Clark Citation2016).
Bill embarked for the USA on the passenger ship RMS Caronia of the Cunard Line, arriving in New York on 24 September 1953. From New York, he travelled by train directly to Madison, Wisconsin, to attend the American Institute of Biological Sciences (AIBS) meeting. Chester Arnold had suggested that the Palaeobotanical Section meeting at the AIBS conference would represent an ideal start to Bill’s fellowship, and that he would establish many contacts there. Bill networked well at Madison and met, among others, Aureal T. Cross (West Virginia University), Robert M. ‘Bob’ Kosanke (Illinois State Geological Survey), Sergius H. ‘Serge’ Mamay (Smithsonian Institution, Washington, DC) and James M. Schopf (Ohio State University). Of these scientists, it was Jim Schopf (1911–1978) who became Bill’s most influential contact on palynology (Cross et al. Citation1995), and Bill became lifelong friends with many of these colleagues. He was most surprised that, at the ‘smoker’ (icebreaker) on the opening night of the meeting, free beer was to be served. After all, this was the American Midwest in the 1950s. He regretted commenting what a good idea the free beer was when, subsequently, Bill discovered that Chester Arnold was a teetotaler.
Chester Arnold was an excellent host and mentor to Bill, and was very helpful and generous with his time, but was never intrusive regarding Bill’s work. Bill was billeted in a small office in an old dental hospital over the road from the Museum of Paleontology at Ann Arbor. He was given unfettered access to Arnold’s laboratory and could macerate samples, cut and section permineralised material, and take photographs. In particular, Arnold made available his collection of Mississippian coal and limestone samples, and Bill extracted lycopod megaspores from some of these. To say the least, this piqued Bill’s interest, and he undertook further solo fieldwork in some of the source areas. Unsurprisingly, Bill later found some of the US species in the Mississippian of the UK (Scott Citation1995, p. 219). Bill also undertook fieldwork with Arnold, notably to a large open-cast coal mine at nearby Grand Ledge, Michigan, where good Pennsylvanian compression fossils could be collected. Arnold was the sartorial polar opposite of Tom Harris while in the field (section 3), and would dress impeccably, sporting a tie and a trilby hat!
During September 1953, Al Traverse, then of the United States Bureau of Mines in North Dakota, visited Chester Arnold and Bill at Ann Arbor. This was the first time that Bill had met Al (Riding et al. Citation2016). The three went out for a day of collecting to Grand Ledge and, after they finished their fieldwork, Al inadvertently locked the car key in the boot which could not be opened from inside the unlocked car. Much to the delight and surprise of his American colleagues (and himself!), Bill hotwired the car with scrap cable from the pit dump and Chester Arnold’s penknife. Bill had never performed this procedure before (Traverse Citation1993, p. 13–14).
In addition to researching, as behoves a diligent postdoctoral fellow, Bill attended Chester Arnold’s palaeobotany course for advanced undergraduates. This was largely based on his major textbook (Arnold Citation1947). Arnold was a superb teacher and Bill thoroughly enjoyed this course. Unusually for the early 1950s, numerous colour slides were used in the lectures and Arnold displayed a huge range of fossil material during the practical sessions. Furthermore, apart from achieving the specific project goals, Commonwealth Fellows had to write a report on an aspect of American life. Unsurprisingly, given his penchant for student politics (section 5), Bill elected to review student government in US universities, a project he found fascinating.
Bill worked hard on the Mississippian megaspores of the Michigan Coal Basin and prepared a manuscript which he gave to Chester Arnold for comment. He was somewhat surprised when Arnold returned it very promptly with only minor changes. Bill was accustomed to the major editorial surgery on his drafts by his ex-supervisor Tom Harris (section 4). Despite the gentle comments of Arnold, the manuscript was given far more robust scrutiny by the journal editor, Robert V. Kesling, before it was published (Chaloner Citation1954b). The other published outputs from Bill’s US fellowship were Chaloner (Citation1956a, Citation1956b).
In the spring of 1954, Chester Arnold helped Bill plan a palaeobotanical road trip from Michigan to California, taking in the maximum number of fossil plant sites. The holders of Commonwealth Fellowships were expected to travel widely in the USA for at least two to three months. Bill’s application was, in summary, ‘to see American palaeobotany’. So, during May 1954 Bill departed Ann Arbor, with snow still on the ground, driving his five-year old pea-green Buick Roadmaster (which had cost $400) on his own grand tour to the west coast and back (). Bill always liked to have his photograph taken with a new car, and throughout his life he made detailed notes of all the cars he owned and drove. On this road trip, he visited William ‘Bill’ Spackman (Penn State University, Pennsylvania), Theodore ‘Ted’ Delevoryas and Wilson N. Stewart (Urbana, Illinois), Henry N. Andrews (St. Louis, Missouri), Robert W. ‘Bob’ Baxter (Lawrence, Kansas), and Daniel I. Axelrod (University of California, Berkeley).
While in Berkeley, California, Bill wanted to meet Ralph W. Chaney, but he was away on fieldwork. Instead, he met a new research student of Chaney’s, Jane Gray (1929–2000). She had recently moved west to Berkeley from Harvard University, Massachusetts, where she had worked with Elso S. Barghoorn on the Miocene palynology of Oregon. Jane was an experienced palynologist who had also worked with Johannes Iversen (1904–1972) of the Geological Survey of Denmark, Copenhagen, on Quaternary angiosperm pollen. She was to undertake research with Ralph Chaney, specifically to study the Paleogene/Neogene pollen associated with Chaney’s leaf fossils. The latter was an expert in Paleogene/Neogene palaeobotany (e.g. Chaney Citation1940). Bill got along well with Jane Gray and they subsequently kept in regular touch. Jane Gray went on to become an expert in Paleogene/Neogene pollen (e.g. Gray Citation1960).
The postdoctoral fellowship in Michigan was the ideal start to Bill Chaloner’s academic career; it gave him a wider perspective and he made many fantastic contacts. He was forever extremely grateful to Chester Arnold for making 1953–1954 ‘a magical year’ (Scott Citation1995, p. 219). Bill’s sojourn in the USA also resulted in him meeting his American wife Judith (Judy) Carroll on the voyage back to the UK in the late summer of 1954 on the ocean liner RMS Queen Mary. Judy was travelling to the UK for the first time, having graduated that summer from the University of Vermont, to take a short course on English literature at the University of London. Bill often recalled that he was sunbathing on deck (he loved the sun) one day, and was clumsily trying to apply sun cream when a beautiful American lady passed by and offered to rub it on him. This chance encounter led to a blossoming romance. Later in 1954, the couple visited Paris where Bill attended the Eighth International Botanical Congress (IBC). Perhaps it is unsurprising that Bill mixed business with pleasure on that trip to France; he went on to attend every IBC until 2005. After the Congress, Bill proposed marriage by letter as Judy was en route back home. Judy accepted, but it was a wrench for her to leave her family behind and emigrate to the UK. Bill and Judy were married in 1955 (section 8; ).
At the Eighth IBC, Bill further extended his network of palaeobotanists and palynologists. He notably met the German palynologists Robert Potonié (1889–1974) and Winfried Remy (1924–1995). Bill had previously corresponded extensively with Remy and his wife Renate, who were experts in Late Paleozoic palaeobotany and, like Bill, had worked on the Carboniferous (Remy Citation1953).
After his postdoctoral fellowship, Bill made regular trips back to the USA. Particularly during his early years at UCL (subsection 9.2.), the Chaloners visited Judy’s parents in Maine most summers. While there, Bill would take the opportunity to attend conferences, give lectures and visit friends such as Harlan Banks at Cornell University, Ithaca, New York, and Jim Schopf at Ohio State University, Columbus.
8. National Service (1954 to 1956)
National Service was the scheme of post-WWII peacetime conscription in the UK. Due to the British involvement in the Korean War, healthy young males were compelled to serve in the armed forces for two years, followed by a reserve period of six months. Bill had absolutely no desire to be drafted in this way, despite having been in the Army Cadet Corps while at school.
After his PhD, Bill knew that he could delay his drafting by undertaking postdoctoral research, and this was a significant factor in his applying for, and accepting, the Commonwealth Fellowship. These were normally offered for two years, and Bill happily agreed to fulfill this commitment. However, the secretary of the Joint Recruiting Board (JRB) of the University of Reading informed Bill that he must return to the UK after one year and serve for two years in the army, thereby fulfilling his commitment to National Service. This was because if Bill did the full two-year fellowship, he would have passed the threshold age of 26 for being called up by the armed forces. The Reading JRB were responsible for ensuring that everyone eligible for National Service was called up immediately after ceasing full-time study. Much to Bill’s intense displeasure, the JRB lobbied the Commonwealth Fund, who then asked Bill to curtail his fellowship after one year. This was specifically so that a Commonwealth Fellowship would not be seen as enabling anyone to dodge the draft. Bill commendably agreed to do this.
So it was that after he returned from the USA and the Eighth IBC in the late summer and early autumn of 1954, Bill undertook two years in the army due to the delay in his National Service. From October 1954, he served as a Gunner and Second Lieutenant in the Thirtieth Royal Artillery Regiment; his first postings were Oswestry, Shropshire, and Ton Vanau, North Wales (). In early 1955, Bill passed his Officer Cadet Training Unit examination, and started training as an officer cadet.
Bill and Judy married at Chelsea Town Hall registry office during a three-day period of special leave in 1955 when they were living in Wales (). The ‘occupation’ entry for Bill on their marriage certificate reads ‘palaeobotanist/gunner’. Their honeymoon in Swanage, on the Dorset coast, was cancelled due to heavy snow. Instead they stayed for two nights at the Ship Hotel in Brighton, before returning to North Wales. Bill was sent to Mons Officer Cadet School in Aldershot, Hampshire, soon after their brief and hastily rearranged honeymoon. Meanwhile, Judy lived in lodgings in London, and Bill commuted there twice a week in his old Austin Seven. Following the marriage, the army gave Bill and Judy the privilege of choosing a posting in Germany, Hong Kong or London. Bill preferred the UK and Judy wanted to go to Hong Kong, so they compromised on Germany! So, in June 1955, Bill was sent to serve the army in Delmenhorst in Lower Saxony, northern Germany. Judy returned briefly to the USA before joining Bill in married quarters in Germany.
Bill was not happy about his National Service at all, believing that it could seriously compromise his career in science, with his contemporaries getting two years ahead of him. However, he was clearly as scientifically active as was possible during his time in the army; a short taxonomic paper about the megaspore Triletes palaeocristatus at that time gave his affiliation as ‘B.A.O.R Germany’. This was Chaloner (Citation1956b), and the acronym stands for British Army of the Rhine. A major highlight during his National Service was when Winfried and Renate Remy sought out and visited Bill in Germany, which helped him keep in touch with his science.
9. University College London (1956 to 1972)
9.1. Choices (1956)
Bill need not have worried that his stint in the army between 1954 and 1956 would adversely affect his later career in science. During his National Service, he was offered three jobs in palaeobotany! Remarkably, all three opportunities were entirely unsolicited. They were: (i) to replace Robert Crookall at the GSGB; (ii) to take over from the retiring Wilfred Edwards at the BM(NH); and (iii) an Assistant Lecturer post in the Department of Botany at UCL. All three were ‘plum jobs’ and Bill was delighted, and somewhat humbled, to have such a fantastic choice. All three offers came with the assurance that the position would await the completion of Bill’s National Service. Given ample time to cogitate, Bill decided on the job at UCL, and started there immediately after his National Service. His starting salary at UCL, ∼£750 per annum, was substantially less than his army pay!
9.2. University College London, 1956 to 1959
9.2.1. The foundations of an academic career
Given Bill Chaloner’s unequivocal academic excellence, and clear upward trajectory, it was inevitable that he would have an academic career (). His first permanent professional position was Assistant Lecturer in the Department of Botany at UCL. Bill’s 16-year tenure at UCL was the beginning of a long and successful association with the University of London that lasted all his career.
Bill’s first boss was the Head of Department, Professor William H. Pearsall (1891–1964), who was replaced by Professor Dan Lewis in 1957. The Department of Botany at UCL had a long association with palaeobotany; John Lindley (1799–1865) was the first Professor of Botany there between 1829 and 1860 (Chaloner and Pearson Citation2005). Lindley was co-author of The Fossil Flora of Great Britain with William Hutton (Lindley and Hutton Citation1831–1837). John Lindley was succeeded by Daniel Oliver (1830–1916) between 1861 and 1888, who in turn was followed by his son Francis W. Oliver (1864–1952) between 1890 and 1925. The latter was an active palaeobotanist at UCL (Andrews Citation1980); for example he collaborated with Dukinfield Henry Scott (1854–1934), with the assistance of Marie C. Stopes, on the recognition of the pteridosperms (Oliver and Scott Citation1904).
Bill followed Francis W. Oliver, and was the only palaeobotanist at UCL at that time; he brought a novel approach, specialising in in situ studies and palaeoecology. Hence, Bill had a wonderful opportunity to build up integrated palaeobotany and palynology, and to plough his own furrow. Bill diligently got on with his duties of researching and teaching in the Department of Botany. He had undertaken significant levels of demonstrating while at Reading (section 4), but had to devote significant time and effort to developing courses and lectures at UCL. For example, he ran an intercollegiate course on Proterozoic to Quaternary palaeobotany (including palynology). All students at colleges of the University of London and from research centres such as the BM(NH) were eligible to attend this course. This module, suitably modified over time, was taught by Bill throughout his career under different course codes (for example B23 at Bedford and Birkbeck colleges, and B323 at RHUL). It did not merely comprise lectures and practicals (including maceration and peeling); the students also had to undertake small research projects. They were taken on field trips and visits to consultancies with laboratories. Field trips included visits to the Jurassic cliffs at and around Whitby (Yorkshire), the Paleogene at Cobham (Kent) and the Isle of Sheppey (Kent), the peat and peat-forming plants at Thursley mire in Surrey, the Pennsylvanian coalfields of Kent and Somerset, and the Royal Botanic Gardens, Kew.
This course on palaeobotany proved very popular due to Bill’s diligent teaching and the way he valued all his students as individuals. Bill continued to teach it long after leaving UCL. One of his students, Thomas M.F. Windle, who took the course in 1973 (when Bill had moved to Birkbeck College, see section 10), eloquently stated:
His teaching style was so compelling, engaging and coherent, so fascinating and so simple that it is no wonder people considered the subject to be soft. Each was an episode in an evolving drama and a lecture would begin with a brief recap of the previous offering in which a mystery had been solved only to lead to another botanical conundrum. The conundrum would be explored and answers uncovered and proffered. The lecture would end with a summary of the lessons learned but a subtle warning that the status quo could not be maintained – but sadly that story would have to wait for another week. No! No Prof you can’t do that! I don’t want to wait till next week! Prof’s lectures were better than any drama or any ‘who dunnit’ and brought with them an unfailing desire to learn, apply scientific rigour and question every aspect of the subject. (quoted in Collinson Citation2017, p. 23).
Ex-students often refer to Bill’s conciseness and his accurate, clear, compelling, convincing and simple delivery. One of us (ACS) took the palaeobotany course as an undergraduate and this led to him undertaking a PhD with Bill. Others followed the same route, for example Carol B. Thomas, a protégé of Kenneth L. Alvin at Imperial College London.
During the late 1950s, Bill continued his PhD and postdoctoral research on Carboniferous palaeobotany and palynology, and published several papers (subsection 9.2.2. below). The Palaeontological Association was formed in 1957, soon after Bill joined UCL, and he welcomed the opportunity to publish some of his Carboniferous research in the first volume of their journal Palaeontology (Chaloner Citation1958b).
In 1957, Marie Stopes asked to visit the Botany Department to view the collection of fossil plants that she had helped to build up from 1899 to 1904 and 1910 to 1920. Marie had been an undergraduate in botany with chemistry and zoology at UCL, graduating with a First in 1902, and was mentored by Francis W. Oliver FRS, then the Head of Department. She also simultaneously studied geology at Birkbeck College in the evenings (Chaloner Citation2008, p. 26). Marie served as an assistant to Francis Oliver, and notably undertook some of the illustrations for his joint landmark publication on the pteridosperms (Oliver and Scott Citation1904). This was prior to undertaking her PhD on the morphology and reproduction of living cycad seeds in Berlin with Karl von Goebel and Ludwig Radelkofer, which was awarded magna cum laude in 1904 (Chaloner Citation1995, Citation2005). Bill gained the impression that Marie was somewhat disappointed by the fossil plant collection, and surmised that her memories of the fossils were superior to the actuality. This visit was about one year prior to Marie Stopes’s death on 2 October 1958 (Chaloner Citation1958a). She bequeathed her scientific library to UCL. The volumes which were duplicated were sold and Bill enthusiastically acquired several of these. He noted with interest Marie’s copious annotations in the margins, some of which were rather strident when she disagreed with the author’s views (Chaloner Citation1995, ). Bill adopted Marie’s trait of adding pithy marginalia on papers (Supplemental data, Appendix 2, Pearson Citation2017, p. 26).
Bill’s work at UCL brought him a well-deserved and rapid promotion to Lecturer in 1958. Also in the late 1950s, Bill obtained funds from the DSIR to visit the eminent authority on Carboniferous megaspores Sijbren J. Dijkstra of the Geological Survey of the Netherlands at Heerlen. While he was in mainland Europe, he also visited Belgium to meet Suzanne Leclercq (Liège) and François Stockmans (Brussels).
9.2.2. Publications at University College London, 1956 to 1959
During the 1950s, while at UCL, Bill published 10 papers (Supplemental data, Appendix 1). Apart from Chaloner (Citation1958a, Citation1959a), an obituary for Marie Stopes and a review of continental drift in a popular science book series, all were on Paleozoic palaeobotany or palynology. Chaloner (Citation1959a) was written well before the discovery of palaeomagnetism and seafloor spreading in the early 1960s. In the 1950s, the deep earth dynamics of continental drift were not known, and it was assumed that the continents had simply ‘ploughed’ across the oceans. Chaloner (Citation1959a) is a review of a controversial topic at the time and Bill came across as a ‘pro-drifter’, using his knowledge of plant provincialism to support the hypothesis.
The first two papers on Paleozoic palaeobotany and palynology were based on his work in Michigan (Chaloner (Citation1956a, Citation1956b). Next, Bill issued his first review paper (Chaloner Citation1957); this was an unillustrated essay comprising synopses of the major publications on Paleozoic pollen and spores at this time. The next four papers are all on Carboniferous material, from England, Ireland, Scotland and the USA (Chaloner Citation1958b, 1958c, Citation1958d, Citation1958e). The latter contribution was especially innovative, and is the subject of subsection 9.3. Chaloner (Citation1958b, Citation1958d) are typical of his careful studies of Carboniferous plants and their in situ megaspores and microspores. Chaloner (Citation1958b) concluded that Selaginellites may have been the dominant floral element which produced Densosporites-rich coals. Bill discovered that the characteristic Pennsylvanian miospore Endosporites globiformis was from the plant which produced Polysporia cones (Chaloner Citation1958d). The same spores had been found in a compression that Bill had described earlier as Lepidostrobus zea (see Chaloner Citation1953b). Subsequently, these specimens were included in Chaloneria belonging to the Chaloneriaceae of the order Isoetales (Pigg and Rothwell Citation1983a, Citation1983b).
At this time, Bill began to work on Devonian palynology, and Chaloner (1959b), a study of some Devonian megaspores from Ellesmere Island, Arctic Canada, represents his debut in this area. In this study, Bill noted a general rise in the average size of megaspores from the Devonian to the Carboniferous, followed by a reduction in the Mesozoic.
9.3. The Neves effect
Two years after joining UCL, Bill made a significant advance in Carboniferous palynology. He turned his attention to the palaeoecology of Carboniferous spores, and published a short note in Geological Magazine (Chaloner (Citation1958e); this was his breakthrough paper. In it, he reinterpreted the data of Neves (Citation1958) on the dynamics of the Pennsylvanian upland flora. Chaloner (Citation1958e) appeared in the same year as Neves (Citation1958); therefore, Bill had come to his conclusions relatively quickly (Supplemental data, Appendix 2). Neves (Citation1958) described the palynofloral changes through a cyclothem or sedimentary cycle (i.e. coal seam, non-marine shale and marine band) in the Pennine Lower Coal Measures Formation [Bashkirian (Langsettian)] of north Staffordshire in central England. Profound differences in the spore associations in these cyclothems were discovered by Neves (Citation1958). The coal-forming phase and the non-marine shale are characterised by low-diversity floras dominated by spores (largely Lycospora which was derived from lycopods such as Lepidostrobus). By contrast, the marine interval is characterised by more diverse associations but is dominated by pollen from Cordaitanthus (largely Florinites). Neves (Citation1958) suggested that the abundant Florinites pollen in the marine phase was most likely to have been derived from marine marginal floras, as opposed to coal swamp vegetation. These data were developed further by Neves (Citation1961).
Bill compared the scenario of Neves (Citation1958) with the earlier account of the Paleogene palynology of Venezuela by Kuyl et al. (Citation1955) – in particular how the pollen-spore floras responded to sea level changes. By analogy with Kuyl et al. (Citation1955), Bill suggested that the process observed by Neves (Citation1958) was a result of Florinites representing quasi-permanent vegetation of extensive forests in the hinterland as opposed to the sea margin. Specifically, when the low-lying coal swamp environments in the Pennsylvanian, dominated by lycopods bearing Lycospora, were inundated by marine incursions, the spore-pollen floras would be substantially affected. At these times, the upland (conifer- and cordaite-dominated) areas would cause the marine muds to be dominated by wind-transported saccate pollen such as Florinites. This was due to the temporary displacement of the proximal onshore swamp settings which yield abundant Lycospora (; Chaloner Citation1958e). When sea levels dropped, the lycopod-dominated coal swamp vegetation again colonised the nearshore area, with spores again dominating the coastal environment. Bill later revisited this work in a short review (Chaloner Citation1961).
This phenomenon, where pollen-spore assemblages and their parent floras fluctuate successively in response to the proximity of the shoreline as a result of sea level variations (specifically where the proportion of hinterland pollen-spores becomes progressively larger moving offshore), was later termed the Neves effect by Chaloner and Muir (Citation1968, p. 139). The Neves effect emphasises wind transportation. It assumes that the majority of miospore production was carried by the wind and deposited in nearshore marine settings. It does not, however, highlight the possible importance of the transportation of miospores into the marine system via fluvial systems (Chaloner and Muir Citation1968; Streel and Richelot Citation1994). This concept was developed by one of Bill’s PhD students at UCL, Marjorie Muir, who investigated whether the Neves effect had operated in the Middle Jurassic Ravenscar Group of North Yorkshire. This includes cyclic sedimentary rocks with a marine phase through to thin coal seams (Muir Citation1965; Chaloner and Muir Citation1968). Despite this, plus indirect lithofacies control on spore-pollen floras in the Jurassic, it was found that a phenomenon similar to the Neves effect could be readily discerned in the Middle Jurassic paralic palaeoenvironments of northern England (Chaloner Citation1968a, ; Chaloner and Muir Citation1968).
Furthermore, changes in pollen-spore floras due to plant successional phenomena in autochthonous situations such as Pennsylvanian coal swamps were termed the Smith effect by Chaloner and Muir (Citation1968) in recognition of the work of the UK palynologist Harold Smith (e.g. Smith Citation1962). A similar phenomenon is the purely climatic von Post effect of Chaloner and Muir (Citation1968). This refers to extensive, regionally climatically forced floral successions such as those observed during the Quaternary (Moore et al. Citation1991). It is typical of Bill’s innate modesty that he thought that Chaloner (Citation1958e), which was very extensively cited, was ‘over-quoted’ (Pearson Citation2017, p. 27).
9.4. Editing the Crookall/Kidston monographs on Carboniferous plants (1959 to 1976)
Robert Kidston (1852–1924) was an eminent and hugely influential palaeobotanist who researched Paleozoic plant fossils. He was an inveterate collector, and had amassed probably the most extensive set of Paleozoic plant specimens ever acquired by an individual. Kidston was appointed as honorary Paleozoic plant consultant to the GSGB in 1880 by Ben Peach (section 6; Crookall Citation1938; Thomson and Wilkinson Citation2009). Unfortunately, Kidston passed away in 1924 while working on the second section of his magnum opus, the memoir Fossil Plants of the Carboniferous Rocks of Great Britain. The first section, which ran to six parts, was already published or in press at that time (Kidston Citation1923a, Citation1923b, Citation1923c, Citation1923d, Citation1924, Citation1925). Section 2, which comprised seven parts, was only around half completed when Kidston died and this represented the majority of his huge legacy of unfinished work. The completeness of the seven parts of section 2 was highly varied; ironically, parts five and six were virtually finished. In the Preface to the final part of section 1, Sir John Flett stated, ‘It is hoped that means will be found to complete the work on the lines he laid down, but this cannot be done without considerable delay’ (Kidston Citation1925, p. 12).
Robert Crookall (1890–1981) was recruited by the GSGB in 1924 in order to complete and edit the second section of Kidston’s Memoir. These were the seven unfinished monographs on the Carboniferous (largely Pennsylvanian) plant fossils of the UK, and this project was termed the ‘Second Section’ of Fossil Plants of the Carboniferous Rocks of Great Britain. Crookall had achieved much prior to the outbreak of WWII in 1939, but the task of finishing and finalising these extremely important manuscripts was far too much for one person, given the huge volume of material involved. The eventual seven volumes comprised 1004 pages, plus 173 plates (Crookall Citation1955, Citation1959, Citation1964, Citation1966, Citation1969, Citation1970, Citation1976). Robert Crookall did his best to complete the Kidston monographs, and achieved a great deal, but none had been published by the time he retired in 1952. Not only was there a prodigious amount of material to edit, but Crookall was very deferential to Robert Kidston, whom he perceived as being infallible and who had godlike status in his eyes. Consequently, Crookall’s reluctance to deviate from Kidstonian orthodoxy slowed the editing process down considerably.
In order to expedite the publication of Kidston’s work, the then Chief Palaeontologist of the GSGB, Sir Cyril James Stubblefield FRS (1901–1999), asked Bill Chaloner to become a consultant in the late 1950s. Bill’s principal task, which lasted until 1976 (by which time he had joined Birkbeck College), was to help revise the Kidston manuscripts and take them through the publication process. Bill agreed, somewhat reluctantly for he did not relish this gargantuan task. He recognised the importance of Kidston’s work, but thought that helping to edit it was ‘a terrible job’. He initially offered to restudy the lycopods from first principles, and this would be his work alone. Stubblefield turned this down; he preferred the monographs to be ‘by Robert Kidston, revised by Robert Crookall, edited and modified by Bill Chaloner’. In spite of this somewhat complex situation, Crookall was to be the sole named author of all the seven volumes. Eventually Bill agreed to simply do an ‘arms-length’ edit of the manuscripts, mainly ensuring internal consistency, and not put anything new or original into them. The vast majority of Bill’s input was in the final five volumes (Crookall Citation1964, Citation1966, Citation1969, Citation1970, Citation1976). Sydney W. Hester MBE, a GSGB geologist, was a great help to Bill with the editing and checked all the references, among other tasks.
Overall, Bill did not particularly enjoy this work, and found it a somewhat odd and uncomfortable undertaking. He often radically disagreed with Kidston, and was frequently considerably irritated by Crookall’s aforementioned steadfast refusal to question Kidston’s views. Specifically, both Crookall and Kidston held very rigid views of palaeobotanical systematics and the species concept, which Bill described (perhaps somewhat harshly) as ‘almost pre-Darwinian’. This slavish adherence to established species concepts by Crookall and Kidston was alien to Bill. He had been taught (correctly) by Tom Harris that species are what we make of them at any one moment, and are not immutable. Harris drummed into Bill that one could modify the designation of a taxon on the basis of the study of new materials, and hence that taxa are iterative concepts. However, despite his misgivings regarding this work, Bill recognised that it was a useful experience and he learned a great deal. The seven tomes comprised volume 4 of the Memoirs of the Geological Survey of Great Britain, Palaeontology. They were all themed; for example, volume 6 is on the Cordaitales and Ginkgoales (Crookall Citation1970). Austin W. Woodland of the GSGB acknowledged Bill in the Preface to Crookall (Citation1976) thus:
The second (editing task) was provided by Professor W.G. Chaloner, FRS, who sacrificed time from research work nearer to his heart to the labour of enhancing the correctness and the usefulness of the book. His unobtrusive and disinterested contributions are gratefully acknowledged. (italics added by the present authors)
Following helping with the Kidston/Crookall manuscripts, Bill continued being a consultant to the GSGB and published several items in their publications (Chaloner Citation1962a, Citation1966; Mortimer and Chaloner Citation1972). He was also asked by the GSGB to examine the late Precambrian fossil Charnia, discovered in 1957 by Roger Mason in Charnwood Forest, Leicestershire (Ford Citation1958). Bill did so, and reported by letter that he did not regard it as a plant.
9.5. Teaching the micropalaeontology MSc course (1959 to 2008)
Bill Chaloner’s expertise and repute as an accomplished teacher and consummate communicator grew rapidly within UCL, and another opportunity presented itself which would last most of his career. During the mid-1950s, the eminent micropalaeontologist Professor Tom Barnard of the Department of Geology was establishing UCL as a major centre for the study of calcareous microfossils (Banner and Lord Citation1982). In 1959, Tom Barnard asked Bill to expand his teaching duties to present lectures and practical sessions on palynology for his recently established MSc course in micropalaeontology. This course spanned all the microfossil groups, but was dominated by foraminifera (taught by Tom Barnard) and ostracods (taught by Eric Robinson).
Bill readily agreed to contribute and he thoroughly enjoyed this work, which of course was outside his parent department. He taught eight lectures on land plant palynology, recalling that marine palynology did not really exist at that time (Manten Citation1966; Riding and Lucas-Clark Citation2016). As a result of his industrial connections at this time, such as Vittorio Roveda (the founder of Paleoservices Limited of Watford), Bill undertook a range of consulting projects, and this also provided material for his MSc students. In the 1950s, the literature on terrestrially derived palynomorphs was relatively sparse; it prominently included Schopf et al. (Citation1944), Potonié and Kremp (Citation1954, Citation1955), Kuyl et al. (Citation1955) and Potonié (1956). Schopf et al. (Citation1944) was an annotated synopsis of Paleozoic spores, and included descriptions and many superb line drawings. By contrast, Kuyl et al. (Citation1955) represented one of the first publications on palynology emanating from the oil industry. At this time, centres of palynology such as Cambridge, Krefeld, Sheffield and Utrecht were being established throughout Europe at least partially due to the increasing demands of industry. Consequently, the early 1960s was a very exciting time to be a palynologist, and Bill deemed himself lucky to have had the opportunity to teach on terrestrial palynomorphs during this watershed era.
Probably as a result of this teaching effort, Bill was able to contribute to a textbook on palynology (Tschudy and Scott Citation1969) with a chapter on Permian and Triassic spores (Chaloner Citation1969). Bill also used the MSc course to attract PhD students, and the majority of his research students at UCL undertook research on widely differing aspects of terrestrial palynomorphs ranging in age from Devonian to Neogene. These included Margaret G. Mortimer (Devonian), Robin F.A. Clarke (Permian), Gerry Orbell (Triassic–Jurassic transition), Marjorie D. Muir (Jurassic), Lynn O. Allen (Palaeocene), Ma Khin Sein (Early Eocene), Jane M. Pallot (Late Eocene and Oligocene) and Michael C. Boulter (Neogene) (). These postgraduate students, and all his subsequent ones, commented how good a supervisor Bill was. Not only did he help them in their respective research projects, he would mentor them in how to present their work at conferences and in scientific writing. Furthermore, Bill enthusiastically encouraged his postgraduate students to attend suitable scientific conferences. He would regularly drive groups of his colleagues and students in a minibus to relevant symposia in the UK and across Europe, and the parties normally camped together.
Table 2. The 29 research students who were supervised or co-supervised by Bill Chaloner. All were students of the University of London except Rosemary Falcon and Keith Fowler. The numerical references in the final column are the EThOS reference numbers for theses. EThOS is the UK’s national PhD thesis repository administered by the British Library; it aims to maximise the availability of PhD theses (http://ethos.bl.uk/About.do). Attempts have been made to locate and curate the microscope slides pertaining to the theses on palynology. Those of Lynn O. Allen, Jane M. Pallot (later Machin) and Ma Khin Sein are housed in the Micropalaeontology or Palaeobotany collections, Earth Department, Natural History Museum (NHM), London; the slides of Lynn O. Allen were donated in 2018. The thesis by Keith Fowler stated that ‘the slides are on file at the Department of Biological Sciences, Portsmouth Polytechnic’. This collection would have included c. 200 Paleogene samples and c. 1200 specimens of modern comparative material. Unfortunately, while writing this article, it has not been possible to contact Keith Fowler. Current staff at the University of Portsmouth have looked for the slides during 2018 but could not locate them. In their opinion, it seems most likely that the slides were discarded decades ago. Brian Daley and Nick Edwards, both formerly of the University of Portsmouth, also thought that the slides had been disposed of. The slides of Aglaoreidia and Azolla published by Fowler (Citation1971, Citation1975a, Citation1975b), and included in his thesis, are housed in the Palaeobotany collection of the NHM. Boulter and Windle (Citation1993) stated that the slides used therein from the work of Marjorie D. Muir (later Curtis) and Thomas M.F. Windle were deposited in the NHM. The slides of Thomas M.F. Windle were located in September 2018 within the material of Michael C. Boulter, now housed in the Micropalaeontology collection at the NHM. At the time of writing, Marjorie D. Muir’s slides have not been located; it is hoped that they are also in the collection of Michael C. Boulter at the NHM.
In the context of Bill’s mentoring of students, it should be noted that he was an insatiable collector and reader of papers on palaeobotany and palynology in many languages at a time when obtaining material, for example in Mandarin and Russian, was very difficult. There was no technology such as photocopiers or scanners in the 1950s and 1960s. Not only did he amass a very large reprint collection (Supplemental data, Appendix 3), he was also intimately familiar with its contents. If asked about any topic, Bill would immediately pinpoint relevant publications in order to allow students to begin their own investigation of the literature. He also encouraged his students not be satisfied with papers only in English, or with a western European approach. Bill urged them to learn languages such as French, German and Russian to help with the translation and understanding of papers which were not written in their mother tongue.
The UCL master’s course on micropalaeontology was run over five decades, finally closing in 2008. Bill’s contributions were unbroken, except for his various sabbaticals; therefore, from the early 1960s onwards, he taught many students land plant palynology. As well as the lectures, the students undertook practical work. Bill would give each of them a rock sample from an unspecified locality (often from the North Sea), and have them prepare it, write a report on it and determine its age (Batten Citation1982, p. 278). Because he was such an effective, inspirational and nurturing mentor and teacher, Bill motivated many individuals, even those who did not pursue palynology as a career. Many graduates of this course who went on to become micropalaeontologists remember Bill’s classes in palynology with great clarity and fondness. Likewise, many graduates became palynologists of great distinction. For example, the Cretaceous palynologist David Batten was first enthused in the subject by Bill Chaloner in the UCL master’s course (Batten Citation1982).
The challenge of teaching palynology in the master’s course stimulated Bill to move away from the Carboniferous in situ studies that had introduced him to the subject while at Reading and Michigan. He read widely and much more generally, especially on stratigraphical aspects. This resulted in research students majoring on palynology such as Robin F.A. Clarke and Marjorie D. Muir (), and some consulting work mainly on material from the North Sea. Specifically, the MSc course experience led Bill to adapt his expertise to new applications such as climate change and oil and gas exploration.
9.6. University College London, 1960 to 1964
9.6.1. To move or not to move?
In 1961, Bill Spackman offered Bill Chaloner the opportunity to be a visiting professor in the College of Earth and Mineral Sciences at Penn State University in Pennsylvania, USA, for one year, which he accepted (Traverse Citation1993). His duties included teaching a course in palynology based on his (albeit limited at that time) experience teaching in the master’s course in micropalaeontology at UCL. This was at the time Bill was writing his magnum opus, the lycopod section of Traité de Paléobotanique, by far the largest item he ever wrote as a sole author (Chaloner Citation1967a). Bill thought that the opportunity at Penn State would be an interesting experience and obtained a one-year leave of absence from UCL. So, at Penn State, Bill taught a master’s course in palynology, with Gilbert Brenner and Daniel Habib among the class of five. Bill also taught an undergraduate course on elementary biostratigraphy to around 150 students in 1961. Apparently, many students took this in order to fulfill their one science requirement on the (perceived) basis that geology was an easy option! Bill enjoyed teaching both courses, especially elementary biostratigraphy because it required him to read up on American geology and palaeontology. In late April 1962, Bill Chaloner and Bill Spackman flew to Tucson, Arizona, to attend the First International Conference on Palynology, organised by T.L. Smiley (McGregor Citation1987). This was Bill Chaloner’s first international conference on palynology and he met many new contacts, including Harry Godwin of Cambridge (West Citation1988).
At the end of the year at Penn State, Bill was offered a job there. He was terribly torn. On one hand, Judy and their two school-age children were all for it. The Chaloners had a great lifestyle with a house on the edge of the campus with, for example, swimming in summer and ice-skating in winter at a nearby lake. However, Bill was not sure; he perceived life at a university in Pennsylvania to be something of an academic backwater. Additionally, the College of Earth and Mineral Sciences strongly emphasised topics such as geochemistry, geophysics, metallurgy and mining geology, and consequently it was not the best department for a palaeobotanist. Despite these factors, he accepted the position and the Chaloner family returned to the UK to make the necessary arrangements for emigration. Naturally, UCL wished to retain Bill and offered him a readership starting in 1963, which he accepted. Additionally, Bill was also able to negotiate the employment of a technician to help with palaeobotanical and palynological preparation at this time. So, with a somewhat heavy heart, Bill sent a telegram to Penn State informing them that he had changed his mind. Some years later, Gerhard O.W. Kremp took up the palynology position at Penn State, where he and others produced the Catalog of Fossil Spores and Pollen (Traverse et al. Citation1970; Riding et al. Citation2016). Kremp did not stay long at Penn State; apparently, he experienced difficulties teaching in his second language and moved to the University of Arizona, Tucson, Arizona. He was replaced by Al Traverse, who was very pleased with the layout of the palynology laboratory that Bill had designed for him there (Riding et al. Citation2016).
The early 1960s were well within the so-called brain drain, an era when many talented UK professionals were tempted into emigration by lucrative job offers in North America and throughout the New World. True to this zeitgeist, yet another opportunity emerged for Bill. Following the job offer by Penn State, he was asked to apply for a faculty position in palynology at the University of California, Berkeley. On the face of it this position had much to offer, such as access to research funding, a generous salary, great research infrastructure and life in San Francisco. Bill’s great friend Al Traverse also applied and both were interviewed, as was a US Quaternary palynologist. Al and Bill were subsequently shortlisted. Berkeley flew Bill out for an extended interview which included giving a seminar and meeting the staff. Bill was highly impressed, but for some reason Berkeley chose not to make an appointment. This was perhaps the result of a profound and prolonged internal rift within the palaeontologists on the faculty at Berkeley. In retrospect, despite absolutely loving California and the many opportunities there, Bill felt glad that he did not join what was a somewhat divided academic group at that time. He returned home and later acted as Secretary for the palaeobotanical events at the 10th 1964 IBC, which was held in Edinburgh.
9.6.2. Publications at University College London, 1960 to 1964
Between 1960 and 1964, Bill published 10 contributions (Supplemental data, Appendix 1). The first of these was a major review paper on the evolutionary origins of vascular plants (Chaloner Citation1960). This was an unillustrated synthesis of publications concerning the early geological history of vascular plants. Bill thoroughly reviewed the literature on Paleozoic macrofossil and mesofossil evidence, including some reports of possible occurrences close to the Precambrian–Cambrian transition. Chaloner (Citation1961) was also a review paper, a short essay on the palaeoecology of Carboniferous spores. Chaloner and Lorch (Citation1960) was his maiden joint paper, and Bill’s first research output outside the Paleozoic. This was a short paper on a new species of the conifer family Cupressaceae, Cupressinocladus ramonensis, from the Lower Jurassic of southern Israel. At the time, this represented the oldest record of the Cupressaceae, but Bill later agreed it might equally belong to the Hirmeriellaceae (Hugh L. Pearson, personal communication).
During the 1960s, Bill began to devote much more of his research effort to palynology, and substantially expanded his range of stratigraphical interest. He worked on the Devonian to Jurassic interval at this time (e.g. Chaloner Citation1961; Chaloner Citation1962a, Citation1962b, Citation1963; Chaloner and Clarke Citation1962; Chaloner and Pettitt Citation1963, Citation1964; Pettitt and Chaloner Citation1964). Chaloner (Citation1962a) represents Bill’s first venture into post-Carboniferous palynology. It is an account of the palaeobotany and palynology of material stratigraphically below the Lias Group (Lower Jurassic) in the GSGB Henfield Borehole, West Sussex, southern England, which had previously been considered to be of Pennsylvanian age. Bill determined that it is latest Triassic to earliest Jurassic, on the basis of the presence of the conifer Hirmeriella muensteri and the pollen genus Classopollis. Chaloner (Citation1962b) is a paper on a new species of lycopod cone, Sporangiostrobus ohioensis, from the Pennsylvanian of Ohio, USA, and its in situ megaspores and microspores. The latter are Densosporites, which are also known from cones of some species of Selaginellites.
Bill continued his work on the Devonian at this time with three papers. The first of these was Chaloner (Citation1963), a short note documenting spores from plant-bearing strata of Early–Middle Devonian age from the GSGB Witney (Apley Farm) Borehole, Oxfordshire, central England. The others were Chaloner and Pettitt (Citation1963, Citation1964); these papers described a seed megaspore, Cystosporites devonicus, from the Upper Devonian of Quebec, Canada, which proved that the fossil record of seed plants extended into the Late Devonian. Chaloner and Pettitt (Citation1963) represented Bill’s debut in prominent generic science journals. Bill then published a short paper with his student Robin Clarke describing the miospore Vittatina hiltonensis from the Hilton Plant Bed (Upper Permian) of Cumbria, north-west England (Chaloner and Clarke Citation1962). The species was also compared with Classopollis. Pettitt and Chaloner (Citation1964) examined Classopollis pollen grains obtained from the pollen sacs of Hirmeriella muensteri from a fissure deposit in South Wales. Transmitted electron microscope analysis indicated an extremely distinctive and elaborate wall structure (Pettitt and Chaloner Citation1964, ).
9.7. University College London, 1965 to 1972
9.7.1. The road most travelled
Bill Chaloner had another opportunity to move out to the west coast of the US when, in the mid-1960s, he was offered a position at a major oil company based in La Habra in the Los Angeles metropolitan area of southern California. Petroleum exploration was expanding at this time and the large oil companies were in aggressive recruiting mode. Despite the lucrative pay on offer (about three times his university salary), and the lure of the Golden State, Bill declined this offer and remained in academia.
Also during the mid-1960s, the University of London sent many leading faculty members on secondments to second-world universities, especially in Africa. They had especially strong links with the oldest Nigerian university at Ibadan. Despite this, Bill was asked to work at the University of Nigeria at Nsukka for around one year between 1965 and 1967. The university at Nsukka had been initiated from scratch by Michigan State University, and the University of London wished to gain influence in this relatively new, American-style university. An administrator at UCL noticed that Bill had done his postdoctoral fellowship at the University of Michigan at Ann Arbor and nominated Bill to go to Nsukka on this basis. He or she did not realise that the University of Michigan at Ann Arbor and Michigan State University were not only different institutions, but deadly local rivals!
Bill consulted with Judy on the potential hazards of taking their three children, who were then aged between 2 and 10, out of school and into the tropics; happily, she was enthusiastic about it. They probably felt that it was the last time they would have a chance of a working spell overseas without it impacting too seriously on their children’s education. The secondment was funded by the Official Development Assistance (ODA), who paid Bill’s salary. His UCL salary continued, so it was financially attractive into the bargain.
Bill was made Professor of Botany at Nsukka and his task was to teach, to run the department and to plan and execute the merger of the departments of Botany and Zoology into a unified School of Biology. He enjoyed all these tasks immensely and was struck by the very happy racial mix in the University of Nigeria at Nsukka, where Africans, black and white Americans, Asians and Europeans mixed together in perfect harmony (). Immediately after the Chaloner family arrived in Nigeria in 1966, the President was deposed by the military. This coup d’état, known as the ‘First Revolution’, was recalled by Bill as being ‘both exciting and scary’. Bill truly relished the opportunity to see at first hand unfamiliar tropical biomes such as mangrove, rainforest and savannah vegetation. Furthermore, the University of Nigeria took full advantage of his consummate teaching skills, and Bill taught subjects at Nsukka which he would never have attempted in London.
Needless to say, Bill could find relatively little time for research in Nsukka but he greatly enjoyed travelling into the savanna, and farther south to the rainforest, to practice botany. Specifically, he collected pteridophytes, which he had agreed to do for the herbarium at the Royal Botanic Gardens, Kew, back in London. Specimens had to be collected in triplicate, i.e. one for Kew, one for the herbarium at Nsukka and one for himself. Bill also visited the mangrove swamps at Port Harcourt by boat with the help of colleagues who worked for Shell in Nigeria. This was the first time that Bill had been able to study tropical vegetation. He also travelled to Ibadan as an external examiner early in the summer of 1966, and was able to see more rainforest to the east of there. He collected palynological samples in the Cretaceous coal near Lagos (this was the main source of electricity in the Lagos area), and from a Paleogene lignite north of the Niger delta. His one piece of research was on the germination of the unique pollen grains of the African oil palm, Elaeis guineensis, which are similar to trilete spores. This was published later in Chaloner (Citation1970a). The relatively unstable nature of Nigeria at that time was manifested again when Biafra in the east attempted to secede from the rest of the country. This caused the Nigerian Civil War (or Biafran War) to break out in July 1967. Luckily for the family Chaloner, this was one week after they returned to the UK.
During 1967 Bill was elected a Fellow of the Linnean Society (FLS). In October 1968, Bill attended the first annual meeting of AASP at Louisiana State University (LSU) in Baton Rouge, Louisiana (Traverse and Sullivan Citation1983, pl. 3/1a). He delivered an invited lecture and met many US-based palynologists for the first time. Bill renewed his acquaintance with George Hart who at that time worked at LSU; after the conference they visited New Orleans. Bill was fascinated by the cultural melting pot that is New Orleans, very different from the Midwest and New England. Bill’s keynote talk at LSU was entitled ‘The evolution of miospore polarity’ and he wrote it up as Chaloner (Citation1970a). He emphasised the evolution from homospory in Silurian plants to heterospory in the Devonian. The next significant rungs on the evolutionary ladder of plant reproduction were the development of the seed habit in gymnosperms during the Late Devonian, and the origin of the angiosperms (Chaloner Citation1970a, ; Bateman and DiMichele Citation1994, ). In 1969, Bill became a member of the Committee for Fossil Plants, after the 11th IBC in Seattle. This is the permanent committee for the nomenclature of fossil plants, and is now termed the Committee on Fossils.
9.7.2. Publications at University College London, 1965 to 1972
During this period at UCL, Bill published 23 scientific items (Supplemental data, Appendix 1). At this time Bill consolidated his position as a globally known researcher on Late Paleozoic palaeobotany and palynology and published nine papers on those topics. The first of these was a brief contribution on Carboniferous megaspores to a GSGB memoir on the area around Ballycastle, County Antrim, Northern Ireland (Chaloner Citation1966). The only other contribution on Carboniferous palynology at this time was a largely biostratigraphical paper on the Mississippian (Tournasian) megaspores and miospores of Leicestershire, central England (Mortimer et al. Citation1970). The samples were from shales interbedded in dolomitised limestones and lacked the otherwise ubiquitous miospore genus Densosporites (Mortimer et al. Citation1970, p. 379). The only other publication on the Carboniferous was a superbly illustrated account of some lycopod macrofossils from southern Ghana (Mensah and Chaloner Citation1971). In this article, the species Archaeosigillaria essiponensis and Lepidodendropsis sekondiensis were established, and the authors concluded that the Lepidodendropsis flora extended much farther south in Africa than was previously known.
Bill also published four papers on Devonian megaspores and miospores at this time. The first of these was a short note on miospores from the Lower Devonian of south Wales (Chaloner and Streel Citation1966). However, the two most significant contributions were Mortimer and Chaloner (Citation1967, Citation1972). The first of these was a largely systematic paper describing nine new megaspore species from the Upper Devonian of the GSGB Wyboston Borehole, Bedfordshire, central England. Mortimer and Chaloner (Citation1967) established the genus Heliosporites, and confirmed the observations of Chaloner (1959) that Carboniferous megaspores are significantly larger than their Devonian counterparts. The megaspore diversity indicated that heterosporous plants were more prevalent in the Devonian than the macrofossil record suggested. Bill was not especially known for his interest in biostratigraphy; however, the authors included a range chart of miospore genera from this section (Mortimer and Chaloner Citation1967, ). Mortimer and Chaloner (Citation1972) is an account of Lower, Middle and Upper Devonian plant fossils and spores from 11 boreholes which penetrated the Mesozoic and Cenozoic cover in England south of the Wash, and was a revised part of the PhD thesis of the first author (Mortimer Citation1967, Citation1969). The associations were comprehensively documented and illustrated; the principal emphasis is on biostratigraphy.
Finally, Bill documented well-preserved material of the lycopod species Cyclostigma kiltorkense from the Upper Devonian of Kiltorcan, Kilkenny, Ireland (Chaloner Citation1968b). This species is morphologically closer to counterparts from the Carboniferous than any other Devonian lycopod and yielded distinctive megaspores attributed to the genus Lagenicula. The only paper on Devonian palaeobotany at this time was Chaloner (Citation1972). This was a short systematic note on two new species of plant (Dawsonites roskiliensis and Svalbardia scotica) as compression fossils from the Middle Devonian of Sloagar, Buness, Fair Isle, north-east Scotland.
Chaloner (Citation1967a) was one of Bill’s masterpieces; it is a comprehensive review of the lycopods in a major treatise on palaeobotany which he also co-edited (Boureau et al. Citation1967), and represented the culmination of years of work on this important group. Boureau et al. (Citation1967) is the second of nine treatises on palaeobotany (Traité de Paléobotanique) produced in France, coordinated and edited by Édouard Boureau of Paris. These volumes are systematic treatments of the major groups of fossil plants, and are written in French. The 365-page chapter by Bill on the lycophytes (class Lycopsida) was translated into French by Mlle. J. Chanel after the submission of Bill’s English manuscript in 1962. R. Brinsden supplied some of the photographs, and Édouard Boureau edited the translated manuscript during the intervening five years. Chaloner (Citation1967a) is divided into seven orders, plus incertae sedis forms. Each genus and species was listed, together with geographical information, line drawings, photographs, stratigraphical details and synonymy lists. Bill included some illustrations of spores (e.g. Chaloner Citation1967a, figs 394, 396, 446, 449, 456). At the end of the systematic section is a brief general and phylogenetic discussion of the lycophytes with an extremely informative spindle diagram (Chaloner Citation1967a, p. 783–785). Bill also produced a much shorter account of the 18 families which then comprised the class Lycopsida as part of a major summary of the fossil record (Chaloner Citation1967b).
In Chaloner (Citation1967c), Bill reviewed the inception of vascular terrestrial plants in the Late Silurian, and their early evolution and morphological development until the end of the Early Devonian based on both macrofossils and spores. Diversity increased steadily during the Devonian and there was a gradual divergence in spore size groups, culminating in heterospory and the seed habit (Bateman and DiMichele Citation1994). He later undertook another major review of the rise of the first terrestrial plants (Chaloner Citation1970b). This was one of his most important review papers; it summarised major events in the early evolution of vascular land plants, their colonisation of the land and their spores during the Middle Silurian to Early Devonian interval (Wenlock to Emsian) and built on the foundations of Chaloner (Citation1960, Citation1967c). He focussed on anatomical developments in the macroplants and the evolution of heterospory in the Devonian. For example, the step-like increase in plant complexity was discussed, including the development of features such as leaves and water-conducting tissues.
Bill clearly enjoyed undertaking review papers, and Chaloner (1968c) is an elegant discourse on the historical development of pre-Quaternary palynology in the UK. He discussed early work, which began in the nineteenth century, on coal palynology and the contemporary research on this topic. The expansion in palynology stimulated by the oil industry from the 1950s onwards was documented, together with sections on techniques such as imaging and sectioning, marine palynology and palaeoecology. In the same year, Bill co-edited a major text on fossil plants (Alvin et al. Citation1968). This major work marked the retirement of Tom Harris from the Chair of Botany at the University of Reading and comprised 22 papers on palaeobotany, including Chaloner (Citation1968b).
Chaloner (Citation1968a) is an essay on the palaeoecology of pre-Quaternary pollen and spores in a volume of reviews on all aspects of biological evolution. After the introduction, Chaloner (Citation1968a) was subdivided into three sections. The first section was based on a PhD thesis on the pollen and spores of the London Clay Formation of Early Eocene (Ypresian) age, and how these compare to the fruits and seeds (Sein Citation1961). Bill supervised this research, and this is his only major work in the Paleogene. Sein (Citation1961) demonstrated that the macroflora of the London Clay Formation is heavily preservationally biased in favour of large and/or robust fruits and seeds, and that the pollen floras are weighted to wind-pollinated types rather than insect-pollinated forms (Chaloner Citation1968a, ). The second section comprised a review of pre-Paleogene pollen-spore palaeoecology. In situ studies and the relationship between pollen-spores and lithology were examined. The latter aspect included the Neves effect which operated in the Pennsylvanian and Middle Jurassic (subsection 9.3.). The final section was a short piece on the interplay of climate, lithology and sea level on the nature of pollen and spore associations in the fossil record. Chaloner and Muir (Citation1968) is also an important contribution, and is discussed in subsection 9.3. This is a review of the use of pollen and spores from land plants in the correlation of coal seams and the interpretation of Quaternary vegetation dynamics. In situ studies of Carboniferous palaeobotany were described, as were the Neves, Smith and von Post effects (subsection 9.3.).
Bill also contributed a short chapter on Triassic pollen and spores (Chaloner Citation1969) to an important textbook on palynology (Tschudy and Scott Citation1969). This represented one of Bill’s relatively rare excursions into the Mesozoic and included a range chart of genera (Chaloner Citation1969, fig. 14-1). Chaloner and Allen (Citation1969) is a review of the use of biochemistry in determining the evolutionary history of fossil terrestrial plants. In the late 1960s and early 1970s, palaeophytochemistry was in its infancy. These authors discussed, for example, the preservation of terrestrial plant fossils and how it is possible to isolate leaf cuticles which often preserve analysable cell architecture. Chaloner and Allen (Citation1969) also discussed how the geochemistry of sporopollenin could improve understanding of the development of the earliest land plants. Bill later revisited and further developed this topic in, for example, Hemsley et al. (Citation1992, Citation1993, Citation1994).
Melville (Citation1969) postulated that angiosperm leaf venation patterns indicate that a group of Permian pteridosperms, the family Glossopteridaceae from Gondwana, were the evolutionary precursors of the flowering plants. Alvin and Chaloner (Citation1970) strongly rebutted this hypothesis, stating that the leaf venation pattern of Glossopteris and its relatives is also characteristic of other plant types including the gymnosperms. There was a reply to the latter paper (Melville Citation1970), but more recent research tends to rule out a direct evolutionary link between the Glossopteridaceae and the angiosperms (e.g. Taylor and Hickey Citation1992, ). Unfortunately, the solution to Charles Darwin’s ‘abominable mystery’, the origins of the angiosperms, still remains frustratingly elusive despite much research on aspects such as cladistics and molecular phylogenetics (e.g. Frohlich and Chase Citation2007; Doyle Citation2015; Sauquet et al. Citation2017 and references therein).
One of Bill’s PhD students at this time was Michael C. Boulter, and together they undertook the first detailed analysis of the palaeobotany of the Brassington Formation of Derbyshire (Boulter and Chaloner Citation1970). This contribution was Bill’s only palaeobotanical venture into the Neogene. Boulter and Chaloner (Citation1970) proposed a Pliocene age for this unit, which had been previously attributed to the Carboniferous, Permian and Triassic. The age of the Brassington Formation was subsequently revised to Miocene–Pliocene (Boulter Citation1971) and, more recently, to Middle–Late Miocene (Pound et al. Citation2012; Pound and Riding Citation2016; Walsh et al. Citation2018).
One of Bill’s final papers while at UCL was Chaloner and Orbell (Citation1971) on the palaeobiological definition of sporopollenin. These authors commented that the use of the term sporopollenin for all palynomorph groups and kerogen types is questionable due to their varied biological origins. Chaloner and Orbell (Citation1971) demonstrated that different palynomorph groups differ in properties such as relative density and that centrifugation using a density gradient can help to concentrate the different types.
10. Birkbeck College, University of London (1972 to 1979)
10.1. Academic life at Birkbeck College
In 1972 Bill changed jobs and moved from UCL, where he had worked for 16 years, to nearby Birkbeck College (now Birkbeck, University of London) on Malet Street, Bloomsbury, to become a Professor of Botany. Bill followed in the footsteps of the eminent Paleozoic palaeobotanist Professor David Thomas Gwynne-Vaughn (1871–1915), who was a lecturer at Birkbeck between 1907 and 1909. He continued to teach the MSc micropalaeontology course at UCL, and this was recognised by Bill becoming a visiting professor there. The chair at Birkbeck completed Bill’s 16-year trajectory through the UK academic hierarchy from assistant lecturer to professor. Life at Birkbeck was profoundly different from life at UCL. Most of Birkbeck’s undergraduate courses are part-time, and nearly all lectures are given in the evening between 6 and 9 pm as most of the undergraduates have full-time day jobs. The college motto is in nocte consilium (study by night). While at Birkbeck, Bill took on the roles of Dean of Science and, later, Vice-Dean.
A major advantage of Birkbeck College was that Bill had time there to undertake research during the day uninterrupted by teaching. Moreover, the college gave him a postgraduate assistant position to help with his expanding research programme. He began to publish widely with these assistants. Holders of this post included, in chronological order, Michael D. Crane, Margaret E. Collinson, Catherine Davies (now Rogerson), Alison Hill and Ann Sheerin. His research students during this period included Hee Young Chun (Mesozoic floras of Korea), Margaret E. Collinson (Paleogene fruits and seeds), Andrew C. Scott (Carboniferous floral ecology), Peter H. Smith (Paleogene fungal spores) and Thomas M.F. Windle (Jurassic palynology). Bill also remotely supervised Rosemary Falcon and Keith Fowler (). Karl J. Niklas visited Birkbeck for one year (1974–1975) to work on the chemistry of fossil plants, having been awarded a Fulbright–Hayes Fellowship (Niklas and Chaloner 1976a, Citation1976b). At the time, Karl was a curator at the New York Botanical Garden. Other visiting scientists at Birkbeck during this time included Klaus Leistikow from Frankfurt-am-Main, Germany (Chaloner et al. Citation1979), A.K. Pal from the Geological Survey of India (Pal and Chaloner Citation1979), Maria Reymanowna and Danuta Zdebska from Krakow, Poland, and Oscar Rösler from Brazil (Rösler Citation1978).
During his tenure at Birkbeck, Bill was elected an FRS in 1976. He was the first pre-Quaternary palynologist to receive this honour (and the only one at the time of writing). The Quaternary botanist, ecologist and palynologist Harry Godwin was made an FRS in 1945 (West Citation1988). Furthermore, several botanists and palaeobotanists who were elected FRS, such as Tom Harris, Francis W. Oliver and Dukinfield H. Scott, had also published on pollen and spores. Bill was delighted and surprised in equal measure about becoming an FRS. This major award is the highest accolade in British science and, being the modest man he was, receiving it truly staggered him. However, Bill was truly buoyed by this endorsement of his research by a vote by the Fellows of the Royal Society.
Bill became interested in the use of the scanning electron microscope (SEM) in the early 1970s. At this time, SEMs were becoming more affordable and he obtained a grant from the Royal Society to buy a Cambridge SEM for the department in order to examine plant compression fossils and plant analogues/replicas (e.g. Chaloner et al. Citation1978). In Chaloner and Gay (Citation1973), rubber latex casts of fossil lycopod stem impressions were analysed using the SEM. This technique revealed the original epidermal structure, even if the cuticle is not preserved. The same technique was used in Chaloner and Collinson (Citation1975a). In this study, the coaly material from a sigillarian stem compression fossil was burned away to reveal a finely preserved impression on the surrounding matrix (Chaloner and Collinson Citation1975a, ). The examination of latex replicas of this surface revealed a dense cover of stomata. Chaloner et al. (Citation1979) is a study of a new Permian lycopod genus, Brasilodendron, from Brazil based on SEM analysis of latex replicas and cuticle preparations. It was found that the thick cuticle of the leaf cushion of Brasilodendron is apparently devoid of stomata.
During 1974 Bill was made an overseas member of the Geological Society of Belgium, and he served as President of the Palaeontological Association between 1976 and 1978. He also became the Chair of the Committee for Fossil Plants at the 12th IBC in Leningrad during 1975.
10.2. Publications at Birkbeck College
During his sojourn at Birkbeck, Bill published 20 papers (Supplemental data, Appendix 1). His principal research focus at this time was integrated Paleozoic palaeobotany and palynology, and the majority of these contributions are on the Devonian. Bill did not undertake significant work on pure palynology at this time. Chaloner et al. (Citation1974) is a detailed account of two Devonian species of the non-vascular genus Spongiophyton from the Devonian of Ghana which has a very thick cuticle indicating adaption to a terrestrial environment. Niklas and Chaloner (Citation1976a) is based around a computer-generated mathematical simulation of the Devonian plant Spongiophyton. This representation of the cellular and growth pattern helped them to analyse this important genus. The plant macrofossils and spores of the Trout Valley Formation (Lower Devonian; Emsian) of Maine, north-east USA, were described by Andrews et al. (Citation1977). Chaloner et al. (Citation1977) is a short account which documents the earliest seed plants from the British Isles. These seed fossils, from the Upper Devonian of Kiltorcan, Kilkenny, Ireland (), are bilaterally symmetrical or platyspermic. This occurrence strongly suggests that the platyspermic and radiospermic gymnosperms had broadly synchronous origins, and were separate since their inceptions. Chaloner et al. (Citation1978) is a comprehensive investigation of two Lower Devonian plants from southern England, Dawsonites arcuatus and Sawdonia ornata, including significant analysis using the SEM.
Bill undertook a joint biostratigraphical review of plant genera in the Devonian (Chaloner and Sheerin Citation1979). In this comprehensive synthesis, the stratigraphical ranges of 71 genera were related to the seven Late Silurian–Devonian plant assemblage zones of Banks (Citation1979) across seven major geographical provinces (Chaloner and Sheerin Citation1979, ). These authors also documented an alternative biostratigraphy based on innovations of vegetative and reproductive characters irrespective of generic assignment (Chaloner and Sheerin Citation1979, ). Careful analysis of the maximum observed axis diameter indicates that there was a general increase in this parameter during the Devonian (Chaloner and Sheerin Citation1979, ). This major compilation allowed an objective analysis of early plant evolution, notably the divergence of several major groups including the lycopods from a primitive rhyniophyte lineage between the latest Silurian and the Middle Devonian (Chaloner and Sheerin Citation1979, ).
Chaloner and Lacey (Citation1973) and Chaloner and Meyen (Citation1973) were comprehensive reviews of the palaeobiogeography and provincialism of terrestrial plants in relation to continental configuration and palaeoclimates during the Carboniferous and Permian periods. Bill and his research assistant Margaret E. Collinson compiled a comprehensively illustrated botanical key to the most prominent Pennsylvanian plant compression fossils in the UK which includes information on relative abundances and stratigraphical ranges (Chaloner and Collinson Citation1975b). This key was subsequently expanded and revised by Cleal and Thomas (Citation1994).
While at Birkbeck College, Bill added two highly significant new strands to his research profile. These were the study of growth rings in wood and interactions between terrestrial arthropods and plants in the fossil record. Tree rings can help elucidate fine-scale palaeoclimatic perturbations and the latter is an excellent example of the study of how plants can record the presence and activities of the coexisting fauna. The first paper on tree rings was co-authored with his PhD student Geoffrey T. Creber, whom he had first met at Chelsea Polytechnic in 1946 (section 2; Chaloner and Creber Citation1973). The wood forming in tree trunks in temperate latitudes normally exhibits a distinct banded structure reflecting seasonality, in contrast with wood from trees in tropical latitudes. In Chaloner and Creber (Citation1973), the emphasis was on the Devonian to Permian. Paleozoic wood from Euramerica exhibits sporadic growth rings, unlike most Mesozoic and Cenozoic counterparts. By contrast, clearly developed growth rings are observed in Permian and Triassic wood from Gondwana. These data can therefore help in discerning palaeolatitude and plate configurations.
Kevan et al. (Citation1975) is the first of several contributions by Bill and his collaborators on the interactions between terrestrial arthropods and plants in the Paleozoic. These authors concluded that co-evolution of the arthropods, fungi and terrestrial plants was evident in the Devonian. Soil-dwelling arthropods at this time, such as mites, myriapods and springtails, probably fed extensively on spores and other plant parts. Kevan et al. (Citation1975) theorised that the increase in the morphological complexity of spores was an evolutionary adaption to promote spore dispersal by arthropod vectors. Furthermore, lesions caused by arthropods are present on some Devonian plant specimens; these may have become sites of fungal and other infections. Bill encouraged research on a variety of topics in his laboratory, and there was much cross-fertilisation of ideas. Work by Andrew C. Scott on Carboniferous coprolites (Scott Citation1977) meshed with Bill’s interest on plant–animal interactions. Furthermore, the discovery of an early conifer preserved as charcoal (Scott Citation1974), and Scott’s subsequent PhD research on Carboniferous charcoal and fire, demonstrated to Bill the need to pursue this topic further. The original inspiration to pursue this topic came from Bill’s time at Reading with Tom Harris.
Chaloner (Citation1976) is a concise review of the evolution of pollen and spore exine. Bill concluded that there are several examples of parallel evolution because certain structures were apparently initiated independently in several plant lineages. In Niklas and Chaloner (Citation1976b), Bill advanced his interest in the use of geochemistry in palaeobotany. In this paper, the authors explored the use of chemical profiles to elucidate the taxonomic affinities of nine genera of Precambrian and Paleozoic plants. For example, analysis of the genera Botryococcus and Sporangites suggested algal and animal affinities, respectively. Chaloner and Richardson (Citation1977) summarised the Devonian successions of south-east England in a comprehensive guide to Devonian stratigraphy of the UK (House et al. Citation1977). Pal and Chaloner (Citation1979) is a paper on a Carboniferous flora from Kashmir. This is a record of Lepidodendropsis from the Lower Carboniferous of Kashmir which is an important link between the western and eastern occurrences of this genus. Bill’s joint analysis of the Cretaceous palynomorph Piriurella elongata proved that this species was of fungal, and not algal, affinities (Smith and Chaloner Citation1979). Bill also used his presidential address to the Palaeontological Assocation in 1975, entitled ‘The palaeoclimatic significance of fossil plants’, to discuss the use of fossil plants for palaeoclimate interpretations; much of this was published in Chaloner and Creber (Citation1990).
11. Bedford College, University of London (1979 to 1985)
11.1. Academic life at Bedford College
Bill worked at Birkbeck College for seven years but eventually tired of the evening teaching sessions, as did Judy. Frequently this was for three nights every week, and Bill would typically not arrive home until around 10 pm. Thus, when he was offered the Hildred Carlyle Chair of Botany at Bedford College, University of London, in 1979, Bill gratefully accepted (Audus Citation2001). Bedford College was originally founded by Elizabeth Jesser Reid in 1849 as a higher education college for women. The Department of Botany at Bedford College was a very congenial workplace; it was set in beautiful grounds in Regent’s Park with a botanical garden, croquet lawn, grass tennis courts, greenhouses and a lake. In the summer, Bill and his team would enjoy regular weekly picnics in the grounds. But best of all, the teaching was entirely during the daytime!
Bill was not the first palaeobotanist/palynologist to work at Bedford College; the renowned Cambridge academic Norman F. Hughes (1918–1994) worked as a lecturer in geology there from 1947 to 1953 (Batten Citation1986). During his tenure at Bedford, Bill had several PhD students including Michael J. Cope who worked on fossil charcoal. In addition, Hugh L. Pearson researched Carboniferous lycophytes (Pearson Citation1986), Carol B. Thomas (inspired by Bill’s undergraduate palaeobotany course) began her research on the evolution of plant spores and Gillian M. Rex undertook experiments on the formation of plant compression fossils. The latter project was again heavily influenced by the research of Tom Harris, and followed on from ideas in Walton (Citation1936). In addition, Geoffrey T. Creber continued his research on growth rings in fossil and modern wood on a part-time basis because he was also Head of Mathematics at University College School, Hampstead, London (). Bill welcomed several postdoctoral researchers to Bedford College including Jane E. Francis, Else Marie Friis and Brigitte Meyer-Berthaud. He also inspired the palaeobotanist Richard Bateman, who took Bill’s undergraduate palaeobotany course at Bedford College.
One of Bill’s undergraduate students from his UCL days, John Holmes, travelled to Montpellier, southern France, to work with Jean Galtier who Bill had met in 1964. This research visit began a long association between London and Montpellier with students visiting both ways. These included Brigitte Meyer-Berthaud working at Bedford College, and several of Bill’s students going to Montpellier. The latter included including Gill Rex from Bedford (and later, when Bill was at RHUL, Rachel Brown, Alan Hemsley and Tim Jones).
In 1981, Bill visited the University of Massachusetts Amherst as a Distinguished Visiting Professor and toured around the USA during some of this visit (). In the same year he was elected President of the International Organisation of Palaeobotany (IOP), and served in this post until 1987; Bill had previously been Secretary of the IOP from its inception until 1977. He also served the International Code of Botanical Nomenclature (ICBN) between 1981 and 1994 as a member of the Editorial Committee for the Sydney, Berlin and Tokyo codes (Voss et al. Citation1983; Greuter et al. Citation1988; Greuter et al. Citation1994, respectively). In 1981, Bill succeeded James F. Schopf as the palaeobotanical specialist on this panel, and he was followed by Judith E. Skog for the St Louis Code published in 2000 (Greuter et al. Citation2000). Note that the ICBN has now been renamed the International Code of Nomenclature for algae, fungi, and plants (ICN) (McNeill et al. Citation2012). A history of botanical nomenclature was given by Nicolson (Citation1991).
Bill received the Lyell Fund from the Geological Society of London in 1980, and was appointed a Trustee of the Royal Botanic Gardens at Kew (Kew Gardens) in 1983. He was also invited to deliver the 13th Birbal Sahni lecture, entitled ‘Plants, animals and time’, at the Birbal Sahni Institute of Palaeobotany, Lucknow, India, in November 1983 (Chaloner Citation1984). During October 1984, Bill was awarded the second AASP Medal for Scientific Excellence, and attended the 17th annual meeting at Arlington, Virginia to receive this honour. He is one of only 10 individuals who have received this award, which is given to persons who have made fundamental contributions to the development of palynology (Demchuk and Riding Citation2008, p. 96). His citation reads: ‘…to honor his innovative contributions to sporomorph and plant paleoecology. His ability to integrate his palynological and paleobotanical observations and insights into new scientific concepts has significantly advanced paleoecological studies in palynology’ (Boulter Citation1985).
Unfortunately, in early 1982, two and a half years after Bill joined Bedford College, the finances of several of the smaller University of London colleges, including Bedford, began to deteriorate substantially. Consequently, Bedford College decided to merge all its departments with their counterparts at Royal Holloway College in nearby Surrey (Wedderburn Citation2001). The finances of Royal Holloway College were also profoundly unhealthy, but a merged entity (named Royal Holloway and Bedford New College) based at Egham and Virginia Water was deemed to be fiscally viable (Prebble Citation2005). During the protracted merger process, Bill and his colleagues at Bedford College commuted between the two sites, frequently teaching alternate days at each location. The final move to RHUL, Bill’s fourth London college, was in 1985. Fortunately, as the Chaloner family lived in Barnes, west London, they did not have to move house.
11.2. Publications at Bedford College
Bill Chaloner’s six-year stay at Bedford College between 1979 and 1985 produced 21 publications (Supplemental data, Appendix 1). He continued to work extensively on Paleozoic macrofloras and, as before, Bill did relatively little research in pure palynology at this stage of his career. Bill always considered that palaeobotany and palynology should be integrated and considered a single discipline, and worked to encourage this culture throughout his career. He rightly felt that different parts of the same organism should not be studied by two groups of scientists. Bill’s only paper on Devonian palaeobotany at this time was Chaloner et al. (Citation1980), a joint paper on the uppermost part of the Bokkeveld Series (Middle–Upper Devonian) at Barrydale, Cape Province, South Africa. Chaloner et al. (Citation1980) documented a lycopod flora and placoderm fish; both biotas were compared to coeval material from the Americas and Gondwana. Bill also co-wrote a short, copiously illustrated popular book on the plant fossils of the Rhynie Chert (Lower Devonian) of Aberdeenshire, Scotland, and its geological significance (Chaloner and Macdonald Citation1980).
El-Khayal et al. (Citation1980) represents the first report of Permo-Carboniferous fossil plants from the Arabian Peninsula. This assemblage exhibits more affinity with coeval floras from Euramerica than from farther south-east, for example Gondwana. The length of leaves and the diameter of stems in three Pennsylvanian species of Lepidodendron were measured by Chaloner and Meyer-Berthaud (Citation1983). These authors found that there is an exponential relationship between these parameters. A novel experimental method of analysing the processes leading to the formation of plant compression fossils and their subsequent potential exposure by fracture was undertaken by Rex and Chaloner (Citation1983) based on plant fossils from the Carboniferous of the UK. Scott and Chaloner (Citation1983) described the leafy shoots and leaves of Swillingtonia denticulata from the Pennsylvanian (uppermost Bashkirian) of West Yorkshire, northern England. This species represents the earliest known conifer, and the material studied is very well preserved due to charcoalification prior to burial. Scott and Chaloner (Citation1983) was based on Andrew C. Scott’s PhD research; a preliminary paper had already been published (Scott Citation1974). This discovery led to the appointment of Michael J. Cope to do a PhD on charcoalified plant fossils.
Chaloner and Sheerin (Citation1981) is a short, pithy piece on the evolution of reproductive strategies in the early terrestrial plants in the Paleozoic. The authors commented on how the earliest vascular plants in the Devonian were homosporous and exhibited an extreme r-strategy, thereby explaining why these floras are cosmopolitan. By contrast, as land plants became larger in the Late Devonian and Carboniferous, selection pressures led to a K-strategy. This led to fewer and larger disseminules (i.e. megaspores then seeds) and substantially increased provincialism.
While at Bedford College, Bill continued his study of charcoal in the fossil record in collaboration with his PhD student Michael J. Cope. Fossil charcoal is a proxy for wildfire and the nature of the palaeoatmosphere, particularly oxygen levels, in the geological past. The initial papers on this topic were by Cope and Chaloner (Citation1980, Citation1981). The first of these described the record of charcoalified plant fragments (fusinite) in post-Devonian sedimentary rocks. Fusinite has a distinctive cellular structure; the cell wall homogenises at temperatures of >300 °C (Cope and Chaloner Citation1980, ). The combustible gases carbon monoxide and methane are produced during the pyrolysis of wood, and they support flames in the burning process. The combustion of carbon monoxide and methane is limited by atmospheric oxygen (Cope and Chaloner Citation1980, ), and it is this relationship between oxygen and charcoal that makes the latter a proxy for the former. Natural wildfire since the Carboniferous is of course a selective process which influenced plant evolution in fire-prone settings. Cope and Chaloner (Citation1980) attracted a comment from Clark and Russell (Citation1981) to which Cope and Chaloner (Citation1981) replied. The collaboration with Michael J. Cope produced two other papers on wildfires in the fossil record (Chaloner and Cope Citation1982, Cope and Chaloner Citation1985).
Bill was one of 11 co-editors of the 1983 version of the ICBN (Voss et al. Citation1983). Together with James D. Lawson, Bill co-organised a Discussion Meeting at the Royal Society of London in May 1984 on environments and biological and geological evolution during the Late Silurian and Early Devonian. The proceedings were subsequently published (Chaloner and Lawson Citation1985a, Citation1985b).
At Bedford College, Bill’s three contributions on tree rings were all substantial papers. Creber and Chaloner (Citation1984a) was a review of growth rings in fossil wood from the Devonian onwards in a textbook on palaeoclimate. This topic, at that time, was significantly under-exploited. The Mesozoic trees which lived in the high palaeolatitudes were discussed due to the higher temperatures which prevailed during the Cretaceous. These floras persisted into the Paleogene, but they migrated equatorwards as the planet cooled during the Late Paleogene and throughout the Neogene. This publication was followed by a major review article (Creber and Chaloner Citation1984b). This is an extensive account of the influence of the environment upon the wood structure of fossil and living trees. The interplay of internal factors such as the action of plant growth regulators and photosynthate supply, together with external (environmental) phenomena, was thoroughly assessed. Creber and Chaloner (Citation1985) focussed on tree growth in the Mesozoic and Paleogene as evidenced from tree ring morphology. It was concluded that the high-latitude polar forests, mainly of conifers and supporting relatively diverse faunas, in this extensive greenhouse interval were able to survive the seasonal light regime due to the relatively equable palaeotemperatures and the continental configurations. This means that axial variations of the planet need not be invoked.
Chaloner (Citation1984) was the publication emanating from Bill’s aforementioned Birbal Sahni lecture. It is an unillustrated, wide-ranging piece which discussed the interactions of animals and plants and indications of co-evolution throughout geological time. Bill concluded this paper with some highly entertaining thoughts on the ecological interplay of the grasses and humans (Chaloner Citation1984, p. 200–201).
Tom Harris passed away on 1 May 1983. He had travelled to India in 1982 and in early 1983 contracted bronchitis on the way back to Lucknow from a field trip to the famous Jurassic plant locality in the Rajhamal Hills. Upon his return to the UK it was clear that he was in very poor health and he had a heart attack the day prior to his death. Bill wrote his obituary for The Times within a few days, and followed this up with an extended biographical memoir (Chaloner Citation1985a). This contribution is both beautifully written and comprehensive; it speaks deeply of Bill’s affection for his mentor. Bill told one of us (JBR) that he learned far more about Tom Harris while writing the obituaries than he had ever known while Tom was alive.
Chaloner (Citation1985b) was a brief comment on two major papers on plant permineralisation (Knoll Citation1985; Scott and Rex Citation1985). For example, Bill opined that both papers assume an overly broad concept of peat; he further commented that silicification can result from profoundly different processes, and that marsh and swamp floras should not be viewed as evolutionary cul-de-sacs. This paper includes some phraseology typical of Bill, viz.: ‘None the less, I assume it is my perogative, indeed my obligation, to seek out some areas of contention, lest our discussion should devolve into mere amiable acquiescence’ (Chaloner Citation1985b, p. 139).
Bill and Andrew C. Scott began a series of collaborations at this time including work on arthropod–pteridophyte interactions (Scott et al. Citation1985). By that time, Andrew C. Scott had moved to Chelsea College in London, where Bill had first studied geology when it was Chelsea Polytechnic (section 2). Scott et al. (Citation1985) presented more evidence of this phenomenon in the Devonian and Carboniferous. For example, the gut contents of Carboniferous arthropods include fragments of lycopod xylem and spores; this is clear proof of arthropod phytophagy. Furthermore, the increase in the numbers of arthropod coprolites means that significant proportions of viable gymnosperm pollen and pteridophyte spores could be widely transported. This has implications for the co-evolution that led to the adaptions later exhibited by the angiosperms.
12. Royal Holloway, University of London (1985 to 1994)
12.1. Academic life at Royal Holloway, University of London
When Bill first arrived at the then Royal Holloway and Bedford New College at Egham in Surrey during 1985, the Botany Department was located at Huntersdale, Virginia Water, which is a short distance (∼1 km) from the main campus. Huntersdale was an irregular collection of buildings including a converted domestic house, where the laboratories were housed, and several linked portacabins. In 1994, the department moved on to the main campus at Egham. The unfortunate set of circumstances behind Bill’s move to RHUL (subsection 11.1) were substantially ameliorated by the very warm welcome the ex-Bedford College Department of Botany staff was given in Surrey. Both cohorts of staff knew each other very well as a result of working together throughout the protracted corporate merger negotiations and process. Many RHUL staff volunteered to share their offices with their new colleagues, and were generally extremely collegiate and helpful. This esprit de corps made for a very positive atmosphere in the new merged Department of Botany. Other departments in the newly amalgamated college were not so fortunate, and had significant teething troubles. Bill was given a spacious office and a well-equipped laboratory, and was able to recruit a new group of research students. He also served on the University of London Senate between 1987 and 1991.
The merger of Bedford and Royal Holloway was not the only union between colleges of the University of London at that time. Most of King’s College merged with Queen Elizabeth College and Chelsea College, University of London, in 1985. However, the Department of Geology at King’s (originally founded by Sir Charles Lyell) merged with those from Bedford and Chelsea, and moved to Royal Holloway and Bedford New College. This new department was originally given the choice of moving to King’s College or Royal Holloway and Bedford New College. However, the offer of a new building and laboratories swung the decision towards RHUL. Bill’s former student Andrew C. Scott therefore arrived in the newly merged Department of Geology, with Bill already having moved to Botany at the RHUL site. For the first year, the two of them shared laboratory facilities and they developed several research projects together. Margaret E. Collinson, another of Bill’s PhD students, also joined the Department of Geology, in 1991, thereby strengthening palaeobotany and palynology at RHUL.
In the late 1980s, more corporate change occurred when Botany merged with Zoology to produce a larger Department of Biology at the main RHUL campus at Egham. The apparently ceaseless zeal for mergers in UK universities continued and, in 1992, the departments of Biochemistry and Biology at RHUL were incorporated into the new School of Life Sciences. Upon its inauguration Bill was made the Head of School, and he remained Head until his formal retirement from RHUL in the summer of 1994.
After Bill’s various job offers in the USA (subsections 9.6.1, 9.7.1) he was appointed the Wilmer D. Barrett Visiting Professor of Botany in the Department of Botany at the University of Massachusetts Amherst between 1988 and 1991. This involved making two one-week lecturing visits each year and Bill greatly valued it as a chance to exchange ideas with many US-based palaeobotanists. In addition to his visiting professorship, Bill received more honours. In 1987 he was made a Corresponding Member of the Botanical Society of America. Bill was also elected a member of the General Committee for Botanical Nomenclature at the 14th IBC in Berlin during 1987, and served on this body until the 18th IBC at Melbourne in 2011. Next, Bill was elected an Overseas Associate of the French Academy of Sciences in 1989. He received the Gold Medal for Botany from the Linnean Society of London in 1991 in appreciation of his service to science (Hawkes Citation1992). Bill had previously served as President of the Linnean Society of London, from 1985 to 1988, when this body celebrated its bicentenary. He was only the sixth palaeobotanist to hold this position (Pearson Citation2017, p. 25). Volume 97(2) of The Botanical Journal of the Linnean Society, published in 1988, was dedicated to Bill in recognition of the work he performed during his presidency. He was also Vice President of the Geological Society of London in 1985–1986, and was awarded their Lyell Medal in 1993. When Bill retired in 1994, he was made Professor Emeritus in the Department of Geology (later named the Department of Earth Science) at RHUL which had been the product of the merger between the Bedford, King’s (whose first professor was Sir Charles Lyell) and Chelsea departments. Chelsea was where Bill first started his academic life (section 2), so the circle was completed. Also in 1993 he stepped down as Chair of the Committee for Fossil Plants at the 15th IBC in Yokohama, when he was succeeded by Robert A. Fensome.
During this period, Bill continued to teach his palaeobotany course to undergraduates. While he was working in central London, transport was never an issue; however, upon moving to RHUL, Bill would collect students from Egham railway station and return them there after the teaching sessions. He also continued to supervise PhD students. These were: Rachel Brown (taphonomy of Mississippian macrofloras, supervised jointly with Andrew C. Scott); Alan R. Hemsley (ultrastructure of Carboniferous megaspores, supervised jointly with Andrew C. Scott); Phillip Holmes (experimental taphonomy of pollen and spores); Timothy P. Jones (fusain, supervised jointly with Andrew C. Scott); Mervyn King (Middle Jurassic cycad seeds from Canada); Jennifer C. McElwain (stomata in fossil plants and CO2 levels throughout the Phanerozoic); Imogen Poole (Eocene pyritised twigs from the London Clay Formation); Peter McAllister Rees (Mesozoic macrofloras of Antarctica, supervised jointly with staff at the British Antarctic Survey); and Carol B. Thomas (evolution and variation of plant spores) (). Mervyn King was a mature student (he was a near contemporary of Bill’s), and researched part-time in the early 1990s. The large permineralised cycad seeds from the Middle Jurassic of the Queen Charlotte Islands, British Columbia, Canada, that he studied were subsequently published by Chaloner and Hemsley (Citation1992). In addition, Bill had postdoctoral researchers including David J. Beerling working on plant stomata and atmospheric CO2 concentrations, and Alan R. Hemsley (jointly with Andrew C. Scott) who researched the chemistry of sporopollenin.
One of his postgraduate students at RHUL, Imogen Poole, recalls Chaloner as
…a gentleman scientist who respected his students and their views, and was as receptive to new ideas and advice as he was to deliver them; a patient supervisor whose philosophy was to guide his pupils whilst giving them room to learn through experimentation, (the inevitable) failures and achievements; an academic whose knowledge covered a vast and enviable cross section of subject areas and disciplines; a stickler and perfectionist; a mentor and counsel. (Collinson Citation2017, p. 32)
12.2. Publications at Royal Holloway, University of London
Bill was as scientifically productive as ever at RHUL, issuing 44 publications between 1986 and 1994. For example, in 1991, his output was especially prodigious, with 10 items (Supplemental data, Appendix 1). He was also more polymathic than ever at this time, exhibiting an especially diverse spectrum of research interests. Bill’s first output from Royal Holloway and Bedford New College was Chaloner (Citation1986a). This was a unique departure for Bill, his only paper exclusively on living pollen. It is a short piece which suggested that prominently sculpted exine in the pollen of entomophilous plants may help the separation of electrostatically charged pollen grains from key surfaces such as the bee or the stigma.
Bill’s continued to work on Paleozoic palaeobotany and palynology; he published six contributions on these topics at this time. Chaloner (Citation1986b) is an essay on the distinction between nomenclature and taxonomy in palaeobotany, and controversies surrounding concepts such as form-genus and organ-genus. It was included in a book on systematics and taxonomy (Spicer and Thomas Citation1986). Bill used Carboniferous taxa such as Lepidodendron, Lepidostrobus and Lycospora as examples (Chaloner Citation1986b, , 5.2), and stated that fossil taxa should continue to be treated differently from living forms. Aspects of this topic were also explored by Boulter et al. (Citation1991). In Chaloner (Citation1986c), Bill discussed the state of knowledge of the entire lepidodendroid tree, particularly in terms of how it functioned and grew.
The evolution of the seed during the Devonian and Carboniferous was tackled by Chaloner and Pettitt (Citation1987) who noted that survival pressure in plant communities at that time favoured K-type reproductive strategies. The consequent need for food reserves led to the polyphyletic rise of heterospory and then to the seed (Chaloner and Pettitt Citation1987, ). The three types of life cycle in vascular plants, i.e. homospory, heterospory and the ‘seed habit’, and which appeared in that order during the Devonian, were also discussed by Chaloner and Hemsley (Citation1991). In Chaloner (Citation1988), Bill presented an elegant review of the nature of the earliest land plants and the timing of their inception in a paper dedicated to the renowned Norwegian botanist Ove Arbo Høeg (1898–1993). The earliest spores in tetrads (then of Middle–Late Ordovician age) were shown to be succeeded by the first cuticle, stomata and xylem tubes, entering the stratigraphical record slightly later (Chaloner Citation1988, ).
Chaloner and Creber (Citation1988) reviewed records of 38 Pennsylvanian to Early Permian fossil plant genera in terms of the information this dataset provides on connections and migratory routes between phytogeographical provinces. This study largely focussed on the use of fossil plant records to determine palaeolatitudinal positions. The five phytogeographical provinces were superimposed onto a Permian plate reconstruction by Chaloner and Creber (Citation1988, ). A detailed investigation of compressed cuticle from the enigmatic land plant Spongiophyton minutissimum from the Lower Devonian of Canada was presented by Gensel et al. (Citation1991). These authors suggested that Spongiophyton may be a transitional grade between the algae and higher plants.
Bill also published on the Mesozoic palaeobotany of Australia, Canada and Sweden. Chaloner and Turner (Citation1987) is a short paper on a new genus and species, Cidarophyton rewanense, a probable lycopod cone axis from the Triassic of Queensland, Australia. In Chaloner et al. (Citation1991), the authors reinterpreted the cuticle and spores of the Triassic plant genus Cycadocephalus as a fern, not a bennettite, in a Festschrift in honour of Winfried Remy who Bill first met in 1954 and who had visited him during his National Service (sections 7, 8). Chaloner and Hemsley (Citation1992) is an interesting documentation of some well-preserved cycad seeds attributed to the species Cycadeocarpus columbianus from the Middle Jurassic (Bajocian) of the Queen Charlotte Islands, British Columbia, Canada. The material was collected by Bill’s friend and colleague from UCL, John H. Callomon (1928–2010), while searching for ammonites.
Bill continued to work on wood growth rings. Creber and Chaloner (Citation1987) compared trees of Late Devonian and Carboniferous age with younger wood from the latest Paleozoic, Mesozoic and Paleogene. The former were shown either to have no growth rings, or to exhibit very weakly developed ones, and hence largely grew in low palaeolatitudes with an inferred virtually seasonless climate. By contrast, younger rock units contain woods from trees which grew at high polar latitudes with relatively equable temperatures and high seasonality and which were shown to possess clear growth rings. In greenhouse intervals, tree growth is possible at the poles because the light availability, despite its seasonality, is perfectly adequate for vigorous tree growth (Chaloner and Creber Citation1989). The significance of tree rings was also discussed in two general accounts of the use of fossil plants as proxies for palaeoclimate (Chaloner and Creber Citation1990; Chaloner Citation1994).
Bill’s research continued to be very varied during his time at RHUL. For example, he co-edited a large volume on the origins of the angiosperms and the implications for their biology (Friis et al. Citation1987a). This book is the proceedings of the International Congress of Systematic and Evolutionary Biology (ICSEB) Conference in 1985 where the speakers were all invited. It comprises 10 chapters, several of which are on the fossil record of flowers and animal–plant interactions, plus an extensive glossary and an index. Bill co-wrote the introduction to this volume (Friis et al. Citation1987b), which was a concise account of angiosperm morphology and evolution. Bill helped to organise a meeting on evolution and extinction in the fossil record held in November 1988, and also co-edited the publication emanating from this event (Chaloner and Hallam Citation1989). Similarly, Bill organised a one-day meeting of the British Ecological Society and the Linnean Society of London on ‘Global change and the biosphere’. Six speakers were invited to lecture on how organisms respond to physical environmental change. The proceedings of this event were published, and Bill provided an introduction (Chaloner Citation1991). Another example of Bill’s adaptability at this time was his co-authorship of Berry et al. (Citation1988) on the development, history and current role of the Linnean Society of London. He also continued to contribute to the various iterations of the ICBN (Greuter et al. Citation1988, Citation1994).
Bill, together with Andrew C. Scott, continued to work on fossil charcoal and its implications. Chaloner (Citation1989) is a short review of fossil charcoal as a proxy for the concentration of oxygen (ρO2) in the atmosphere. Bill and Andrew jointly supervised a PhD student, Timothy P. Jones, to advance research into charcoal in the fossil record. The occurrence of charcoal and abundant terrestrial plant life from the Devonian onwards indicates that atmospheric ρO2 has varied between 13% and 35%. Jones and Chaloner (Citation1991) attempted to establish the validity of these percentages experimentally, and to help to discriminate between charcoal (fusain) produced by pyrolysis and inert wood formed by other means. Evidence of pyrolysis comes from the homogenisation of cell walls and increased reflectance as seen in polished blocks under oil.
Chaloner (Citation1990) is a contribution in the journal Science in Public Affairs. In a wide-ranging review, Bill attempted to contextualise contemporary global warming and sea level rise with global environmental changes in the geological past for a general audience. He stresses throughout that coping with perturbations in the natural environment is a natural part of life on the planet. Bill explained that, based on past glacial cycles, we are around halfway through the present interglacial and noted that our present fear of short-term global warming is somewhat of a paradox in this context in the long term. Moreover (he argued), the prospect of greenhouse warming in the coming decades and centuries is arguably preferable to the presumably inevitable next glacial phase. In conversation, Bill frequently espoused the hypothesis that the relatively recent anthropogenically driven increase in greenhouse gases may help to postpone the next glacial interval. However, this contention was not included in Chaloner (Citation1990).
Bill and Andrew C. Scott continued to work on arthropod–plant interactions. Chaloner et al. (Citation1991) is a concise account of the evidence for this phenomenon throughout the Paleozoic and Mesozoic. Some Early Devonian vascular plant fossils reveal traces of feeding activity by animals. This paper stressed the evidence from coprolites for spore-eating by arthropods, and that most of the spores which have passed through the digestive canal remain viable. The nature of leaf feeding throughout the geological record was also explored. Scott et al. (Citation1992) is one of the most comprehensive publications on Paleozoic and Mesozoic arthropod–plant interactions; coevolution, feeding, reproduction, shelter and transport were reviewed. These authors included a range chart of the known occurrences of all post-Silurian arthropod–plant interactions (Scott et al. Citation1992, fig. 53). The final section is a stratigraphical review of this topic divided into nine subsections (Scott et al. Citation1992, appendix 1).
Together with his Natural Environment Research Council (NERC) postdoctoral researcher, David J. Beerling, Bill opened a new strand of enquiry between 1990 and 1993. This was the study of stomatal density and its direct relationship with the atmospheric concentration of carbon dioxide (ρCO2). The inspiration for this line of enquiry was the publication of Woodward (Citation1987), who reported that stomatal numbers on the leaves of trees in the UK had declined since the start of the industrial revolution. This was linked to the ∼50 ppm increase in ρCO2 since the pre-industrial era. Bill immediately realised that stomatal density and numbers on fossil leaves could be used as biosensors of ρCO2 in the geological past. This was the leverage for Beerling’s NERC-funded postdoctoral fellowship with Bill and Michael Tooley of the University of Durham. Information from both ice cores and stomatal density and numbers helped to link glacial to present ρCO2 levels at this time. Bill and David attempted to link global environment to plant evolution. This effort was further stimulated by Berner (Citation1993), who modelled the effects of tree evolution on ρCO2 fluctuations during the Phanerozoic. Nine publications on this topic were issued between 1991 and 1994 by Bill, David Beerling and others (Supplemental data, Appendix 1). Bill became extremely interested in the link between CO2 concentrations and climate, and contended that a detailed knowledge of past changes would help understand and predict future perturbations. The first of these articles was Beerling et al. (Citation1991). In this preliminary study, the leaves of dwarf willow (Salix herbacea) from the last glacial–deglacial transition were used to model long-term plant responses to changing levels of ρCO2 by using stomatal density and index. The entire topic was reviewed in Beerling and Chaloner (Citation1992). The response of stomatal density to changing levels of atmospheric CO2 can be evaluated by four types of investigation. These authors also discussed the variability of stomatal density within and between species, and whether observed differences reflect acclimatisation or genetic adaptation. The latter point was discussed in more detail by Beerling and Chaloner (Citation1993a).
David Beerling, Bill Chaloner and their collaborators then produced a series of four papers on the species-specific responses to changing climate, ρCO2 and temperature of dwarf willow (Salix herbacea), English oak (Quercus robur) and olive (Olea europaea) (Beerling et al. Citation1992, Citation1993a; Beerling and Chaloner Citation1993b, Citation1993c). Beerling and Chaloner (Citation1993b) used olive leaves from the tomb of Tutankahmun in Egypt to calculate the ρCO2 at the time of the late Pharaoh. Beerling et al. (Citation1993b) is the first stomatal density record which extends to >140 ka, i.e. back to the penultimate glacial stage. It was demonstrated that stomatal density decreased, thereby improving water use efficiency, as a response to long-term increases in atmospheric ρCO2. Beerling and Chaloner (Citation1994) compared the stomatal density record since the last glacial maximum with the ice core record from Antarctica. The pattern of CO2 change in both these records is very similar although there are some minor anomalies. Bill’s final PhD student Jennifer C. McElwain continued this research on stomata (; see subsection 13.2). In her studies of plant stomata throughout geological time, McElwain made pioneering discoveries in the use of this proxy in conjunction with biogeochemical models (e.g. Chaloner and McElwain Citation1997). For example, she used data from the charcoalified leaves of Swillingtonia from the Pennsylvanian described by Scott and Chaloner (Citation1983).
Bill collaborated on several studies on molecular palaeobotany, specifically concerning the geochemistry of sporopollenin. Bill and Andrew C. Scott obtained a grant from the NERC Ancient Biomolecules Initiative to employ their former PhD student Alan R. Hemsley as a postdoctoral researcher to investigate the chemistry of pollen and spores and to determine whether plant groups could be identified by differences in their sporopollenin chemistry and if this complex biopolymer can survive diagenetic changes. Hemsley et al. (Citation1992, Citation1994) used 13C solid-state nuclear magnetic resonance (NMR) to investigate the composition of fossil and modern sporopollenin. Significant differences were discovered between the sporopollenins of different taxa and, particularly, between fossil and living material. Hemsley et al. (Citation1993) found that sporopollenin obtained from seed megaspore membranes is slightly different in composition from that of pollen from the same plant type.
13. Later life (1994 to 2016)
13.1. Life and work after 1994
Bill formally retired from RHUL in the summer of 1994, at the end of the 1993–1994 academic year (). He was given a dinner which brought together colleagues and former students from around the world and at which he was presented with a volume of research papers. The after-dinner speech was given by his great friend Al Traverse (Traverse Citation1993).
Like most active exponents of the earth sciences, Bill remained extremely productive and requested that he continue to have office and research facilities following his retirement. Because he had been the first head of the School of Life Sciences, this request for emeritus status was eminently reasonable. Bill’s former research students and colleagues in the Department of Geology at RHUL, Margaret Collinson and Andrew Scott, made the case for Bill to be made an honorary member of staff to Derek Blundell, then the Head of Department. This was readily agreed, and Bill was given an office and access to the Palaeobotany Research Laboratory. Bill was also made an Honorary Fellow of RHUL at this time. When Andrew C. Scott retired in 2012, he and Bill shared an office, began new research on spores from Carboniferous cave deposits and started to plan a major conference on fire for the Royal Society (Scott et al. Citation2016).
Bill continued with a very wide range of teaching during retirement. This included training undergraduates at the American University in London, Birkbeck College, RHUL and UCL. A major component of this was Bill’s lectures for the third-year undergraduate course in palaeobiology at RHUL, which is co-ordinated by Margaret E. Collinson. He stepped down from this at the end of the 2014–2015 academic year (Collinson Citation2017, p. 22). Bill was also able to continue to present his lectures on terrestrial palynology as part of the master’s course in micropalaeontology at UCL, which he absolutely loved, until its curtailment in 2008 (subsection 9.5). He also lectured, on palynology and other topics, for the MSc courses in petroleum geology at Herriot-Watt University in Edinburgh and RHUL. In addition, Bill took every opportunity to deliver public lectures and organise field trips for a wide range of societies and students.
This honorary position in the Department of Geology (now the Department of Earth Sciences) proved to be a very conducive environment for Bill in retirement. He was able to choose when he worked, and could continue his research in palaeobotany. He continued to undertake relatively little palynology late in his career. However, in retirement he was typically scientifically productive, and published 41 papers (Supplemental data, Appendix 1). Bill profoundly appreciated the opportunity to continue both research and teaching in his post-retirement years. He commented how much he enjoyed the opportunity to exchange ideas with the younger generation. In 1996 Bill was awarded the T.N. George Medal by the Geological Society of Glasgow and, in 2005, he was presented with the Lapworth Medal of the Palaeontological Association. During retirement, Bill continued to be an enthusiastic attendee of scientific conferences, and frequently met with colleagues and ex-students ().
Bill continued to pursue his love of gardening, swimming, tennis and travel in retirement; he also found the time for classes in watercolour painting, and even tried his hand at pottery and winemaking. He was quite an accomplished artist, often selling his paintings for charity. One commission Bill received was to paint the Temple of Bellona at Kew (Pearson Citation2017, p. 27). He also loved his family holidays, whether it be skiing or in the sun; if there was any hint of sunshine, Bill would strip to the waist! Bill and Judy did not visit the USA so much during Bill’s retirement. They would typically holiday in the Mediterranean area, frequently around Montpellier, southern France, where Bill could visit his palaeobotanical colleague Jean Galtier whom he first met in 1964 at the 10th IBC in Edinburgh.
13.2. Later publications
Bill Chaloner’s 41 post-retirement publications, between 1995 and 2016, are typically diverse and include several review articles and textbooks. An example of the latter is Moore et al. (Citation1996), which is an undergraduate text on global environmental change. The authors stressed that an understanding of natural global change on geological timescales is crucial in order to assess the impact of relatively recent human activities. Moore et al. (Citation1996) was entirely based on undergraduate teaching that Bill had undertaken to deliver with colleagues at King’s College London. Some of these lectures were given via the ‘Live-Net’ remote link from RHUL.
Bill wrote three articles on Marie Stopes at this time (Chaloner Citation1995, Citation2005, Citation2008). The first of these was his earliest publication during retirement (Chaloner Citation1995). This is in a commemorative volume to the famous American Carboniferous palaeobotanist William (‘Bill’) Culp Darrah (1909–1989) (Lyons et al. 1995). This tome was focussed on Carboniferous palaeobotany in the early twentieth century. Chaloner (Citation1995) discussed the palaeobotanical work of Marie Stopes, i.e. between 1903 and 1935, focussing on her work in North America. In 1910, the Canadian authorities asked Marie to undertake a restudy of the Fern Ledges Flora of New Brunswick. The age of this Paleozoic assemblage was somewhat controversial at the time. Largely on the basis of her collection of specimens from Duck Cove, Marie Stopes determined that the Fern Ledges Flora is Pennsylvanian (and not Silurian or Devonian as had been previously reported) in age (Stopes Citation1914). Chaloner (Citation1995) also discussed Marie Stopes’s claim to have first discovered and recognised coal balls from the USA, and her pioneering work on coal petrography. Ten years later, Bill wrote a review of Marie Stopes’s palaeobotanical work in a textbook on the history of palaeobotany (Chaloner Citation2005). He acknowledged that her contribution to women’s rights and making the case for contraception far exceeded her impact of her work on fossil plants. Marie Stopes attempted to popularise botany and palaeobotany (Stopes Citation1906, Citation1910) and undertook pioneering work on, for example, coal macerals and their terminology, the earliest angiosperms and the formation of coal balls. Finally, Bill wrote up a lecture he had given on Marie Stopes as Chaloner (Citation2008) where, again, he summarised her impact as a palaeobotanist.
In the same vein, Chaloner and Pearson (Citation2005) wrote an account of the nineteenth-century botanist and palaeobotanist John Lindley (1799–1865). The latter was best known for Lindley and Hutton (Citation1831–1837), a comprehensive (three-volume) account of the Carboniferous to Pleistocene macrofloras of the UK entitled The Fossil Flora of Great Britain. In this landmark publication, these authors systematically treated nearly 300 species of fossil plants. This was not simply a catalogue; the authors also discussed experimental taphonomy, the origin of coal, palaeoclimates and plant evolution. Furthermore, they were the first to describe the nitric acid maceration method for isolating and preparing cuticles from plant compression fossils, and using these to illustrate the structure of cuticle in volume 2 of Fossil Flora (Chaloner Citation1998). John Lindley only published three other contributions on palaeobotany, largely as he had many interests in neobotany such as orchidology.
Chaloner’s work using stomatal densities to track the levels of atmospheric ρCO2 was continued with his final PhD student Jennifer C. McElwain, and later with Margaret E. Collinson and Chinese colleagues on Ginkgo. As mentioned previously, the density of stomata on leaves has an inverse relationship with CO2; this has been proven in modern plants and used in the Paleogene to Quaternary fossil record. McElwain and Chaloner (Citation1995) extended this work into the Paleozoic. They measured the stomatal density and index of four species of Early Devonian, Pennsylvanian and Early Permian plant fossils, and compared the data with those from nearest living equivalent (NLE) plant species. The observed changes in the fossil stomatal data support other geological evidence, such as carbon cycle modelling and stable isotopes, of a marked fall in ρCO2 levels from the Early Devonian to the latest Pennsylvanian (McElwain and Chaloner Citation1995, ). The data in McElwain and Chaloner (Citation1995) were also considered in a more general account of the use of the fossil plant record in assessing global climatic change (Chaloner and McElwain Citation1997).
McElwain and Chaloner (Citation1996) undertook a similar study of Middle Jurassic plant species compared to their NLEs and found that stomatal data were consistent with significantly elevated ρCO2 levels compared to today. This theme was continued by McElwain (Citation1998) in a volume on vegetation–climate–atmosphere interactions co-edited by Bill Chaloner (Beerling et al. Citation1998). McElwain (Citation1998) presented new estimates of ρCO2 levels for the Middle Eocene and reviewed previous data from Late Paleozoic and Middle Jurassic plants. Chaloner (Citation1999a) is a concise, wide-ranging review of the evolution of the carbon cycle and includes a section on stomatal density, the origin of the planated leaf, and wildfire. Chen et al. (Citation2001) showed that the stomatal ratios of fossil Ginkgo leaves track ρCO2 variations during the Jurassic and Cretaceous.
As mentioned previously, Bill undertook relatively little research on pure palynology at this time – indeed, since leaving UCL in 1972. In retirement he only published four papers on this topic (Hemsley et al. Citation1996; Chaloner Citation1999b, Citation2013; Mander et al. Citation2012). Hemsley et al. (Citation1996) investigated the geochemistry of some megaspores of Carboniferous lycophytes using 13C magic-angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy. The composition differs from that of the extant lycophyte megaspores. Other studies on fossil material such as fern spores also revealed substantial compositional differences. Chaloner (Citation1999b) is a short piece on the formation of plant and terrestrial palynomorph compression and impression fossils in sediments. Mander et al. (Citation2012) investigated the ultrastructure and botanical affinity of the morphologically distinctive Late Triassic to earliest Jurassic palynomorph species Ricciisporites tuberculatus. The distal colpus and the characteristic nature of the wall indicate a gymnospermous affinity. Arguably, the most interesting of his palynological ventures at this time is Chaloner (Citation2013), a review of three palynological enigmas. These were the puzzling similarity between the external ornamentation of bryophyte and pteridophyte spores and angiosperm pollen, the function of the multiple apertures of angiosperm pollen and the global increase in striate bisaccate pollen grains in the Permian and Triassic despite the macrofloras exhibiting strong provincialism.
Bill kept up his research into the record of wildfire in the geological record. Jones et al. (Citation1997) is on the terminology applicable to all aspects of fire-altered plant matter (i.e. examination, production and usage). The relationships between fire products and a proposed nomenclature were given (Jones et al. Citation1997, , p. 19–21). In the same volume, Robinson et al. (Citation1997) reviewed the pre-Quaternary record of wildfire, which extends back to the early history of plants on land. Case examples were given such as the hypothetical first fire which may have been as early as the late Precambrian, fuelled by desiccated aquatic algae. Our current understanding of wildfire through time has been published in a volume dedicated to Bill (Scott Citation2018b). Scott et al. (Citation2010) is a comprehensive account of plant fossils from organic-rich siliciclastic sediments of Pennsylvanian age, which have infilled Ordovician limestones, in Illinois, USA. Much of the plant remains are relatively unaltered and charcoal, largely from conifers, is prominent in the uppermost beds. These authors developed geochemical data to prove that wildfire helped to preserve these plant fossils. Together with colleagues Andrew C. Scott, Claire M. Belcher and Christopher I. Roos, Bill organised a Royal Society scientific discussion meeting on ‘The interaction of fire and mankind’ in September 2015 (Scott et al. Citation2016). As part of this event, Roos et al. (2016) gave an account of how humans live with natural wildfire at local, national and international scales, the effect of climate change on fires, and many other related topics such as the health consequences of smoke plumes from wildfires.
Bill’s work on plant nomenclature and taxonomy was continued during his later life (Chaloner Citation1999c, Citation2004; Chaloner et al. Citation1998). However, the many and various research topics that Bill took up since the 1980s somewhat limited his work on palaeobotany. He only did a limited amount of pure palaeobotany in retirement. Chaloner (Citation1999d) is on two immature specimens of the tree fossil Archaeopteris from the Upper Devonian of Canada and Ireland. Fletcher et al. (Citation2004) used carbon isotope (13C) analysis to investigate the enigmatic terrestrial Devonian organism Spongiophyton. This technique was previously used by Jahren et al. (Citation2003) to assign this genus to the lichens. Fletcher et al. (Citation2004) rebutted this hypothesis when they discovered that the isotopic composition of Spongiophyton and extant lichens, liverworts and mosses is indistinguishable. Bill co-edited a major volume on the research of Charles Darwin on the evolution of flowers (Crane et al. Citation2010). This work emanated from a discussion meeting at the Royal Society as part of the celebrations to mark the bicentenary of Darwin’s birth and the 150th anniversary of the publication of On the Origin of Species. Darwin had wide-ranging interests in botany, and Crane et al. (Citation2010) comprises a series of review papers on diverse topics including the early history of angiosperms. Another taxonomic commentary was Chaloner and Kenrick (Citation2015), which demonstrated that Captain Robert Falcon Scott’s ill-fated Terra Nova Expedition discovered the plant genera Glossopteris and Nothofagus from Antarctica.
Beerling et al. (Citation2001a) continued the theme of the evolution of the planated leaf first mentioned by Bill in Chaloner (Citation1999a). These authors commented that megaphyll leaves, with their distinctive branching veins and planate overall morphology, first appeared in the latest Devonian. This was ∼40 million years after the inception of leafless, simple vascular plants and coincided with the aforementioned fall of ∼90% in atmospheric ρCO2 levels during the Late Paleozoic. Two comments on this paper were published by Hedrich and Steinmeyer (Citation2001) and Tanner (Citation2001), and the original authors replied to these (Beerling et al. Citation2001b). Bill built upon this theme in Chaloner (Citation2002, Citation2003). The latter is a copiously illustrated major review on the role of CO2 in plant evolution. Bill stressed how plant life cycles carbon in the natural environment and how carbon can be sequestered by coal and limestone in the geosphere. Widespread carbonate and coal deposition, and high levels of photosynthesis, were considered to have caused the reduction in atmospheric CO2 in the Late Paleozoic. Terrestrial plants adapted to this botanically induced change via a marked increase in stomatal density and the evolution of large, planated leaves. The feedback system of wildfire introduced a natural constraint on oxygen levels which are a corollary of elevated ρCO2. Two papers were then issued on the topic of the origins of leaves (Osborne et al. Citation2004a, Citation2004b). Both of these further investigated the substantial temporal gap between the earliest land plants and the development of large megaphyll leaves. The former is a morphometric study of 300 specimens which conclusively demonstrates a 25-fold enlargement of leaf blades in two separate plant clades (Osborne et al. Citation2004a, ). Osborne et al. (Citation2004b) is a comprehensive review of the relationship between megaphyll leaf evolution and falling atmospheric CO2 levels, with a detailed and well-illustrated appraisal of the former.
Chronologically, Bill Chaloner’s final publication was an appreciation and obituary of his great friend Al Traverse (Riding et al. Citation2016). Al and Bill were near-contemporary giants of palaeobotany and palynology, who lived on either side of the Atlantic, and had similarly distinguished academic careers (; section 7). Hence, Bill was scientifically active late in his life; he was planning new work until a few weeks before he passed away.
14. Overview and conclusions
Bill Chaloner had a great start in life. Bill doubtless was inspired by his high-achieving parents and siblings. He seems to have inherited his eloquent oral and written communication skills from his father and mother, Ernest and Lenore Chaloner. Bill clearly found his professional niche early on when he discovered a love of the natural sciences while at school. He developed a sound background in botany and geology, and decided palaeobotany was his true passion. His bachelor’s degree, majoring in botany, was an ideal precursor to his PhD on the in situ spores from British Carboniferous lycopods, supervised by Tom Harris. Bill’s postdoctoral fellowship working with Chester Arnold in Michigan built on his PhD. He was extremely fortunate to have two very supportive academic mentors in Tom Harris and Chester Arnold (sections 3, 4, 7). Both stressed to him the need to link megafossils and macrofossils, and Bill constantly advocated the need for palaeobotany and palynology to be unified. The guidance from Harris and Arnold, fused with Bill’s prodigious talent, formed the bedrock of a stellar scientific career.
Bill began work at University College London (UCL) in 1956, and he stayed with the University of London through all of his 38-year professional career and into retirement, working at four colleges. Most of his research at UCL was on Paleozoic palaeobotany and palynology. He began working on the Devonian while there, and undertook occasional excursions into younger material. Bill gave a hint of the future diversification of his interests when he collaborated on research into angiosperm evolution and sporopollenin. A major paper at this time was on the environmental controls of the distribution of Carboniferous pollen and spores (Chaloner Citation1958e). Later he undertook review papers on this and other topics; these are characterised by their clarity, diversity, originality and perceptiveness. In the early 1960s Bill began teaching palynology in the micropalaeontology MSc programme at UCL. During the 1960s, he was promoted to Reader and undertook visiting professorships in Nigeria and the USA.
Bill accepted the Chair of Botany at Birkbeck College in 1972. A major honour arrived in 1976, when he became only the second palynologist to be elected a Fellow of the Royal Society (FRS). He continued to mainly work on Devonian and Carboniferous palaeobotany, and undertook less work on pure palynology. However, after seven years, Bill moved to Bedford College in 1979. While there, his research interests diversified substantially. He began to work on, for example, arthropod–plant interactions, growth rings in wood, and charcoal and wildfire. The move to Bedford was relatively short-lived due to a protracted merger with Royal Holloway, University of London (RHUL). Bill began full-time work there in 1985 and formally retired in 1994. While at RHUL, Bill kept in touch with Devonian and Carboniferous palaeobotany, but continued with his wide smorgasbord of research interests and added to them further. Notably, he began to work on the density of stomata in plants, global and climatic change, and molecular palaeobotany. Bill worked as Professor Emeritus at RHUL up to his passing in 2016. In retirement, he was typically scientifically productive over a wide spectrum of research interests. and are a summary of his career highlights and a list of his research students, respectively.
It is extremely difficult to fit all of Bill Chaloner’s achievements into one article (Scott and Collinson Citation1993). Bill was asked to review departments and institutes abroad including Palaeobotany in Montpellier, France, Botany at Trinity College Dublin, Ireland, and the Birbal Sahni Institute of Palaeobotany in Lucknow, India, all of which remain important today. Throughout his career at the University of London, Bill was frequently in demand to sit on internal committees and panels. He also volunteered his services to many scientific committees. These include the Antarctic Research Committee and the Fossil Plant Committee of the International Association for Plant Taxonomy. Bill also sat on many boards for the Natural Environment Research Council (NERC) and the Royal Society, including the NERC Council, several steering committees for NERC Special Topics and the Terrestrial Life Sciences Grants Committee. The NERC Special Topics included biomolecular palaeontology and the palaeoclimate of the last glacial cycle. Similar tasks included being a specialist advisor to the House of Lords Subcommittee for Science and Technology on biological systematics research and being a Trustee of the Royal Botanic Gardens, Kew. Bill also chaired the Royal Society Publications Committee, and compiled the British Bibliography of Palaeobotany for many years. Furthermore, he undertook voluntary editorial work for many journals, including Advances in Botanical Research, Annals of Botany, Biological Sciences, Journal of Evolutionary Biology, Journal of Historical Biology, Notes and Memoirs of Fellows of the Royal Society, Palaeontographica Abteilung B, Paléobiologie Continentale, and Philosophical Transactions of the Royal Society. Bill has, naturally, had fossil taxa named in his honour. These include the Carboniferous lycopod family and genus Chaloneriaceae and Chaloneria, respectively, and the Carboniferous spore species Lycospora chaloneri (see Pigg and Rothwell Citation1983a, Citation1983b; Scott and Hemsley Citation1993).
Bill Chaloner was a remarkable man. It is very difficult to do justice to Bill the person in a piece such as this because he was blessed with a veritable plethora of positive attributes. Bill Chaloner was analytical, approachable, caring, charming, charismatic, considerate, eloquent, energetic, engaging, enquiring, enthusiastic, generous, humorous, incisive, intellectual, interesting, kind, knowledgeable, lively, modest, patient, personable, polite, polymathic, practical, self-effacing, sociable, supportive, talented, thoughtful, unassuming, understanding, unflappable, unpretentious, urbane, warm and witty in equal measure. This is emphatically not a hagiographic or over-sentimental description; all those fortunate to have known Bill will fully endorse all these ‘Chaloneresque’ qualities (Traverse Citation1993, p. 15). His great friend Alfred Traverse gave a very moving and personal account of Bill, liberally sprinkled with amusing and interesting anecdotes, subtitled ‘A man for all subjects’ (Traverse Citation1993). For example, Traverse (Citation1993, p. 15) opined that Bill’s very slight Demosthenean lisp added to his oratorical appeal.
Bill was a veritable all-rounder. Very few people in academia can combine virtuosity in administration, editorship, teaching and research. Bill was consummate at all four, and this is typical of a man whose interests were hugely wide ranging. He was a great linguist and had a fantastic memory as well. He was sought after by committees for his effectiveness as both a leader and a team worker. Many ex-students recall Bill Chaloner clearly and fondly as a massively inspirational instructor and mentor. For example, his research student Tom Windle stated that Bill was ‘the finest communicator I have ever come across’ (Collinson Citation2017, p. 23). Bill was emphatically not elitist, and would very happily spend time with anyone with an interest in palaeobotany and palynology whatever their perceived status. His research record speaks for itself (Supplemental data, Appendix 1).
Like all good scientists, Bill Chaloner was good at both fine detail and the bigger picture. The former largely (but not exclusively) was done early in his career, for example his in situ palynology, and the latter (such as global change and palaeoatmospherics) came later. However, his success is not all due to his outstanding scientific talent. Bill was single-minded when necessary, and was a total completer-finisher; he quickly and forensically analysed complex situations and pushed elegant solutions through to their completion. He personally knew a vast array of scientists, not just botanists, palaeobotanists and palynologists. It must be stated here that Bill tried to achieve a good work–life balance. He was a great family man and had keen interests outside science such as music, tennis and travel.
All this is not to say that Bill did not have a steely side to his psyche; for example, he was an extremely exacting, but fair, peer reviewer. His assessments typically were a balanced mix of criticism and generosity – a difficult line to tread. Specifically, Al Traverse recalled being somewhat startled upon seeing red-pencilled remarks such as ‘balderdash’ and ‘rubbish’ from Bill Chaloner, who was one of the critical readers appointed by the publisher, in the margins of the first draft of the textbook Paleopalynology (Traverse Citation1988). Al specifically commented on Bill being a ‘very thorough, and very tough and frank editor’ (Traverse Citation1993, p. 14). Apparently, he could also be an assertive driver (Traverse Citation1993, p. 15). Bill’s daughter Sarah concurs, and recalled that Judy could hardly bear to be driven by him!
Bill Chaloner’s life was celebrated at East Sheen Cemetery Chapel on 1 November 2016. An Acer tree was planted in his memory at the Royal Botanic Gardens, Kew, soon after Bill’s passing. RHUL commemorated Bill’s life on 4 November 2017. At this event ‘male’ and ‘female’ Ginkgo trees were planted in his memory in the RHUL Arboretum, and a memorial research fund was established in Bill’s honour. Bill predeceased his wife of over 60 years by only 10 months; Judy Chaloner passed away in August 2017. Bill and Judy Chaloner are survived by their children Caroline, Michael and Sarah, six grandchildren and one great-granddaughter, with more on the way. They will both be profoundly missed by their family, and the entire community of palaeobotany and palynology worldwide.
Note added after the proof stage
Following the acceptance of this contribution, the authors discovered Creber and Chaloner (Citation1990), an article co-written by Bill Chaloner during his time at RHUL. Creber and Chaloner (Citation1990) is a comprehensive, unillustrated review of the environmental factors which influenced the production of secondary xylem by the vascular cambium. This is the main growth layer of most plants which produces both the phloem and the xylem. The several phases of cambial activity were discussed, as were environmental effects on the quality and quantity of wood produced by trees. Creber and Chaloner (Citation1990) is one of nine chapters in Iqbal (CitationCitation1990), a volume specifically on the vascular cambium. Iqbal (Citation1990) is an update of a book on the same topic by Philipson et al. (Citation1971). This discovery of Creber and Chaloner (1990) means that Bill Chaloner was the author of 177 scientific contributions, and not 176 as was stated in the main paper.
Notes on contributors
JAMES B. RIDING is a palynologist with the British Geological Survey (BGS), in Nottingham, UK. He undertook the MSc in palynology at the University of Sheffield, and several years later Jim was awarded a PhD by the same institution. In 2004 he was awarded a DSc by the University of Leicester, where he studied as an undergraduate. Jim’s scientific interests include the Mesozoic–Cenozoic palynology of the world, palaeoenvironmental palynology, palynomorph floral provinces, forensic palynology, preparation techniques, the history of palynology, and the morphology, systematics and taxonomy of dinoflagellate cysts. Jim is a past Director-at-Large and President of AASP – The Palynological Society, and became Managing Editor of Palynology in 2004.
ANDREW C. SCOTT is a palaeobotanist, palynologist and fire scientist, and is Emeritus Professor of Geology in the Department of Earth Sciences at Royal Holloway, University of London, UK. Following a BSc in geology at Bedford College, University of London, he undertook his PhD under Bill Chaloner in the botany department at Birkbeck College University of London on the ecology of Carboniferous vegetation, graduating in 1976. Andrew then was appointed as a lecturer in geology at Chelsea College (later Royal Holloway) University of London. He was awarded a DSc in 2002, was a visiting professor at Yale University, USA (2006–2007), and was awarded the Gilbert Cady Award by the Geological Society of America in 2007. Andrew currently works on the geological history of wildfire and Carboniferous terrestrial ecosystems.
MARGARET E. COLLINSON is a plant palaeobiologist in the Department of Earth Sciences, Royal Holloway, University of London. UK. Margaret was a research assistant to Bill Chaloner for one year, after which Bill supervised her PhD at Birkbeck College, University of London. Her interests focus on Paleogene floras, especially the morphology and systematics of plant mesofossils, and applying these in palaeoenvironmental analysis in order to reconstruct former greenhouse worlds and biotic responses to climate change during the Paleogene. Margaret was president of the International Organisation of Palaeobotany (IOP) between 2004 and 2008, and she was awarded a Distinguished Fellowship of the Botanical Society of America in 2015.
SUPPLEMENTARY_INFORMATION_Bill_Chaloner_list_of_major_publications_latest_file.docx
Download MS Word (18.8 MB)Acknowledgements
Some of the information used in this contribution was taken from an interview with Bill Chaloner by JBR at UCL held on 16 December 2002 for the AASP Oral History Project. JBR sincerely thanks the staff of the British Geological Survey (BGS) library for help in locating many items of literature. ACS was given full access to Bill’s personal archive and family photographs, and he thanks Bill’s sister Joan and his children Caroline, Michael and Sarah for their help. MEC thanks all the former postdoctoral researchers, research students and visiting scientists who helped to compile Collinson (Citation2017), and therefore for materially contributing to this article. Regarding the palynology slides from theses by Bill’s students (), MEC thanks Lynn O. Allen for agreeing to, and helping to organise, the donation of her slides to the Natural History Museum (NHM) in London; Peta Hayes also helped in arranging this. Michael C. Boulter, Brian Daley, Nick Edwards and Tom M.F. Windle helped regarding the possible whereabouts of palynology slides. Peta Hayes, Mark Lewis and Stephen Stukins searched for slides at the NHM. Finally, former and present staff of the Schools of Biological Sciences and Earth and Environmental Sciences at the University of Portsmouth looked for the slides of Keith Fowler. The authors thank Jan A.I. Hennissen (BGS), Hugh L. Pearson (EDF Energy) and an anonymous reviewer for their very helpful comments on initial drafts of the manuscript. James B. Riding publishes with the approval of the Executive Director, British Geological Survey (NERC). Bill Chaloner’s collection of scientific papers is now stored at BGS, Nottingham, UK (Supplemental data, Appendix 3). This article was written with the full support of the Chaloner family. The reproduction of some parts of Neves (Citation1958) in Appendix 2 of the Supplemental data is with the kind permission of Cambridge University Press, License Number 4270260274566, and the approval of the current editor of Geological Magazine, Peter Clift (LSU, Baton Rouge, USA). Neves (Citation1958) can currently be accessed and downloaded at: https://www.cambridge.org/core/services/aop-cambridge-core/content/view/7F4D618E2678DCEB794B4F608443CA23/S0016756800062488a.pdf/upper_carboniferous_plant_spore_assemblages_from_the_gastrioceras_subcrenatum_horizon_north_staffordshire.pdf.
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The authors have no potential conflicts of interest.
Related Research Data
References
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- Chaloner WG. 2008. Marie Stopes—palaeobotanist. Open University Geological Society Journal. 29:26–30.
- Chaloner WG. 2013. Three palynological puzzles. International Journal of Plant Sciences. 174:602–607.
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- Chaloner WG, Collinson ME. 1975b. An illustrated key to the commoner British Upper Carboniferous plant compression fossils. Proceedings of the Geologists’ Association. 86(1):1–44.
- Chaloner WG, Cope MJ. 1982. Interaction of plant evolution, wildfire, atmospheric composition and climate. Third North American Paleontological Convention, Proceedings. 1:83–85.
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- Chaloner WG, Creber GT. 1988. Fossil plants as indicators of late Palaeozoic plate positions. In: Audley-Charles MG, Hallam A, editors. Gondwana and Tethys. Geological Society Special Publication. London: Geological Society. 37:201–210.
- Chaloner WG, Creber GT. 1989. The phenomenon of forest growth in Antarctica: a review. In: Crame JA, editor. Origins and Evolution of the Antarctic Biota. Geological Society Special Publication. London: Geological Society. 47:85–88.
- Chaloner WG, Creber GT. 1990. Do fossil plants give a climatic signal? Journal of the Geological Society, London. 147(2):343–350.
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Appendix
This is a list of all taxa below genus level which are mentioned in the text, with their respective author citations. The 28 species are listed alphabetically below in three groups.
Extant plants and their common names
Elaeis guineensis Jacq. (African oil palm)
Olea europaea L. (olive)
Quercus robur L. (English oak)
Salix herbacea L. (dwarf willow)
Fossil plants
Archaeosigillaria essiponensis Mensah & Chaloner Citation1971
Cidarophyton rewanense Chaloner & Turner Citation1987
Cupressinocladus ramonensis Chaloner & Lorch Citation1960
Cycadeocarpus columbianus Dawson 1873
Cyclostigma kiltorkense Haughton 1855
Dawsonites arcuatus Halle 1916
Dawsonites roskiliensis Chaloner Citation1972
Hirmeriella muensteri (Schenk 1867) Jung 1968 [previously Cheirolepis muensteri (Schenk 1867) Schimper 1870]
Lepidocarpon waltonii Chaloner Citation1952
Lepidodendropsis sekondiensis Mensah & Chaloner Citation1971
Lepidostrobus zea Chaloner 1953
Sawdonia ornata (Dawson 1871) Hueber 1971
Spongiophyton minutissimum Kräusel 1954
Sporangiostrobus ohioensis Chaloner 1962
Svalbardia scotica Chaloner Citation1972
Swillingtonia denticulata Scott & Chaloner Citation1983
Fossil sporomorphs
Cystosporites devonicus Chaloner & Pettitt Citation1964
Endosporites globiformis (Ibrahim 1932) Schopf, Wilson & Bentall Citation1944
Lagenicula horrida Zerndt 1934
Lycospora chaloneri Scott & Hemsley Citation1993
Piriurella elongata Cookson & Eisenack 1979
Ricciisporites tuberculatus Lundblad 1954
Triletes palaeocristatus (Chaloner 1954) Chaloner Citation1956
Vittatina hiltonensis Chaloner & Clarke Citation1962